Re: [Elecraft] K3 - Power cable voltage drop
As Bob has pointed out, power drop is not the factor in the voltage to
an Elecraft transceiver.
No matter what the supply voltage may be, the K2/K3/K3S/KX2/KX3 will
attempt to produce the output power requested by the power knob setting.
Those transceivers actually measure the output power rather than the
drive level as is done by many other transceivers.
The problem is that the transmit IMD increases as the voltage drops, so
running with a higher voltage results in a cleaner signal on the air.
Of course, if you are an "all knobs right" operator, you may notice a
bit of a drop in the maximum power available on some bands. Instead of
114 watts, you may get only 95 or 100 watts, but that is extreme.
I recommend that you do not set the power knob above 100 watts in any
case. Use the maximum setting only for testing into a dummy load.
The difference between 114 watts and 100 watts is only 0.57 dB and will
not be noticed on the far end of the transmission.
73,
Don W3FPR
On 12/28/2019 5:32 PM, Bob McGraw K4TAX wrote:
It is not quite that simple. Power drop is not really a factor.
The operating range of the radio, from specifications, is 11 volts
minimum to 15 volts maximum. Thus with a 4 volt operating range, a 1
volt drop represents a 25% change. Within this range of 11 to 15 volts
the radio will attempt to deliver 100 watts by demanding the required
amount of current from the power supply. Thus the three resistances in
series example, as I stated earlier, with the middle one {radio} being a
variable value.
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Re: [Elecraft] K3 - Power cable voltage drop
It is not quite that simple. Power drop is not really a factor.
The operating range of the radio, from specifications, is 11 volts
minimum to 15 volts maximum. Thus with a 4 volt operating range, a 1
volt drop represents a 25% change. Within this range of 11 to 15 volts
the radio will attempt to deliver 100 watts by demanding the required
amount of current from the power supply. Thus the three resistances in
series example, as I stated earlier, with the middle one {radio} being a
variable value.
Therefore the resistance of the DC power cables will then cause more
voltage drop to occur as the current demand increases. This has been
noted to cause the transmitter IMD {Inter-Modulation Distortion} to
significantly increase. Much has been written here regarding attaining
lowest IMD while operating at near maximum rated voltage. A word of
caution, NEVER allow the power supply to exceed 15 volts. It is very
important to maintain minimum voltage drop with the power cables and
anything else in the path. Those power distribution strips are horrible
in this regard and should NEVER be used to power the radio. The radio
should always be connected direct to the power supply terminals. No
exceptions.
For this and other reasons, I have my power supply set to 14.8 volts at
no load. In transmit with 100 watts output and current of 17.5 amps,
the voltage indicated by the radio is 14.5 volts or 0.3 volt drop {14.8
- 14.5 = 0.3}. The calculated resistance of my power cables is then E
/ I = R or 0.5 / 17.5 = 0.017 ohms.
In conclusion, it is NOT power output that is of concern.
73
Bob, K4TAX
On 12/28/2019 1:49 PM, shull2...@gmail.com wrote:
At what point does a drop in input power become significant? Does a 1.0v loss
translate to 10 times less output power than a 0.1v loss?
-Original Message-
From: elecraft-boun...@mailman.qth.net On
Behalf Of Bob McGraw K4TAX
Sent: Saturday, December 28, 2019 1:07 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] K3 - Power cable voltage drop
Actually 1 ohm of total resistance from a 14V source and a 20A load would be
more than excessive. More like a 0.01 ohm is 0.20 volt drop for 20 amps. I x
R = E
View it as 3 series resistors across a 14 V source. R-1 is the DC POS lead
resistance, the radio which is a variable resistance as R-2, and
R-3 which is the DC NEG lead resistance. Therefore, the voltage at the radio
is equal to the IR drop being the sum of R-1 and R-3.
73
Bob, K4TAX
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Re: [Elecraft] K3 - Power cable voltage drop
At what point does a drop in input power become significant? Does a 1.0v loss translate to 10 times less output power than a 0.1v loss? -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Bob McGraw K4TAX Sent: Saturday, December 28, 2019 1:07 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop Actually 1 ohm of total resistance from a 14V source and a 20A load would be more than excessive. More like a 0.01 ohm is 0.20 volt drop for 20 amps. I x R = E View it as 3 series resistors across a 14 V source. R-1 is the DC POS lead resistance, the radio which is a variable resistance as R-2, and R-3 which is the DC NEG lead resistance. Therefore, the voltage at the radio is equal to the IR drop being the sum of R-1 and R-3. 73 Bob, K4TAX On 12/28/2019 11:26 AM, Michael Walker wrote: > For measuring voltage drop.. I would measure the voltage drop from the > Plus lead of the Power supply to the plus lead on the back of the > radio while in full load TX (FM or RTTY). > > It should be less than 0.1 or 0.2 of a volt. > > Then, do the same on the Negative Lead. You should see the same > answer (assuming Negative DC doesn't find an alternative path). > > Those numbers should add up to the same voltage drop total. > > As a reminder. It only takes 1 ohm of loss in the cable/fuses to > significantly impact your full power out. > > Mike va3mw > > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to shull2...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Actually 1 ohm of total resistance from a 14V source and a 20A load would be more than excessive. More like a 0.01 ohm is 0.20 volt drop for 20 amps. I x R = E View it as 3 series resistors across a 14 V source. R-1 is the DC POS lead resistance, the radio which is a variable resistance as R-2, and R-3 which is the DC NEG lead resistance. Therefore, the voltage at the radio is equal to the IR drop being the sum of R-1 and R-3. 73 Bob, K4TAX On 12/28/2019 11:26 AM, Michael Walker wrote: For measuring voltage drop.. I would measure the voltage drop from the Plus lead of the Power supply to the plus lead on the back of the radio while in full load TX (FM or RTTY). It should be less than 0.1 or 0.2 of a volt. Then, do the same on the Negative Lead. You should see the same answer (assuming Negative DC doesn't find an alternative path). Those numbers should add up to the same voltage drop total. As a reminder. It only takes 1 ohm of loss in the cable/fuses to significantly impact your full power out. Mike va3mw __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
For measuring voltage drop.. I would measure the voltage drop from the Plus lead of the Power supply to the plus lead on the back of the radio while in full load TX (FM or RTTY). It should be less than 0.1 or 0.2 of a volt. Then, do the same on the Negative Lead. You should see the same answer (assuming Negative DC doesn't find an alternative path). Those numbers should add up to the same voltage drop total. As a reminder. It only takes 1 ohm of loss in the cable/fuses to significantly impact your full power out. Mike va3mw On Sat, Dec 28, 2019 at 11:00 AM Don Wilhelm wrote: > Better precision than a battery can be found by using a precision > voltage regulator. Take a look at the Precision Voltage Source on my > website www.w3fpr.com. > > 73, > Don W3FPR > > On 12/27/2019 5:53 PM, Bill Frantz wrote: > > A simple reality test for a volt meter is to measure a fresh battery. > > Zinc/carbon or Alkaline should show about 1.56 volts. (I learned this > > test from the bias setting instructions for a Dynakit Stereo 70 > > amplifier. They built the amp so the test point read 1.56 volts when the > > bias is correctly set and suggested calibrating your meter with a > > battery. In that era, the zinc/carbon battery was what ran almost all of > > the flashlights (torches for for English speakers) in the world. > > > > 73 Bill AE6JV > > > > On 12/23/19 at 11:30 PM, rmcg...@blomand.net (Bob McGraw K4TAX) wrote: > > > >> A good, known accurate DVM is an asset to any station. Use it to > >> determine if the others are accurate. There are several good brands > >> available. A DVM that is not accurate is worse than no DVM at all. > >> My choice of many years ago is my Fluke 77. After I tapped it with > >> too much voltage, I sent it to Fluke for repair and calibration. I am > >> confident when I make a measurement it is accurate without question. > > - > > Bill Frantz| The first thing you need when | Periwinkle > > (408)356-8506 | using a perimeter defense is a | 16345 Englewood Ave > > www.pwpconsult.com | perimeter. | Los Gatos, CA > 95032 > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to donw...@embarqmail.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to va...@portcredit.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Better precision than a battery can be found by using a precision voltage regulator. Take a look at the Precision Voltage Source on my website www.w3fpr.com. 73, Don W3FPR On 12/27/2019 5:53 PM, Bill Frantz wrote: A simple reality test for a volt meter is to measure a fresh battery. Zinc/carbon or Alkaline should show about 1.56 volts. (I learned this test from the bias setting instructions for a Dynakit Stereo 70 amplifier. They built the amp so the test point read 1.56 volts when the bias is correctly set and suggested calibrating your meter with a battery. In that era, the zinc/carbon battery was what ran almost all of the flashlights (torches for for English speakers) in the world. 73 Bill AE6JV On 12/23/19 at 11:30 PM, rmcg...@blomand.net (Bob McGraw K4TAX) wrote: A good, known accurate DVM is an asset to any station. Use it to determine if the others are accurate. There are several good brands available. A DVM that is not accurate is worse than no DVM at all. My choice of many years ago is my Fluke 77. After I tapped it with too much voltage, I sent it to Fluke for repair and calibration. I am confident when I make a measurement it is accurate without question. - Bill Frantz | The first thing you need when | Periwinkle (408)356-8506 | using a perimeter defense is a | 16345 Englewood Ave www.pwpconsult.com | perimeter. | Los Gatos, CA 95032 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donw...@embarqmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
A simple reality test for a volt meter is to measure a fresh battery. Zinc/carbon or Alkaline should show about 1.56 volts. (I learned this test from the bias setting instructions for a Dynakit Stereo 70 amplifier. They built the amp so the test point read 1.56 volts when the bias is correctly set and suggested calibrating your meter with a battery. In that era, the zinc/carbon battery was what ran almost all of the flashlights (torches for for English speakers) in the world. 73 Bill AE6JV On 12/23/19 at 11:30 PM, rmcg...@blomand.net (Bob McGraw K4TAX) wrote: A good, known accurate DVM is an asset to any station. Use it to determine if the others are accurate. There are several good brands available. A DVM that is not accurate is worse than no DVM at all. My choice of many years ago is my Fluke 77. After I tapped it with too much voltage, I sent it to Fluke for repair and calibration. I am confident when I make a measurement it is accurate without question. - Bill Frantz| The first thing you need when | Periwinkle (408)356-8506 | using a perimeter defense is a | 16345 Englewood Ave www.pwpconsult.com | perimeter. | Los Gatos, CA 95032 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I would leave it at 4.96 as that tells me it was set at some point (from 5.00 default). However, if you think the internal metering is wrong, you could double check it if you have a calibrated meter. Valid range of ADC REF setting is 4.75 to 5.25 and I typically see the correct value around 4.85 to 5.05. To experiment, I checked at 5.25 and 4.75 Set at 5.25 the internal volt meter displayed 14.2V. Set at 4.75 it showed 12.9V That is a 1.3 volt swing so it is worth setting properly. Keith WE6R On 12/26/2019 3:39 PM, Mike Flowers wrote: Hi Keith, Mine reads 4.96, so should it be set to 5.0 or left alone? Thanks. - 73 and good DX de Mike, K6MKF, NCDXC Secretary -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Keith Trinity WE6R Sent: Thursday, December 26, 2019 15:25 To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop Notes for all; Check the K3 config menu item "ADC REF". If at 5.00 it is probably at default. (if at 4.00 a glitch occurred, probably during FW update, and will FUBAR the internal metering. Set to 5.00 or read on). (I check this during checkout, so if it has been in for Service, it should be OK). Higher accuracy of the K3 items like the internal Volt-Meter can be had if this is set properly. With a known external meter on Pin 2 to ground of the 15 pin ACCY connector; Go into config menu ADC REF and set it. Also you can stick your probes into the Anderson connectors at the back of the radio during full power TX to see the actual voltage to the radio. (I have a digital LED meter connected with small wires to the Anderson supply wire right at the back of the radio on my K3 test bench). Keith WE6R __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to mike.flow...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Hi Keith, Mine reads 4.96, so should it be set to 5.0 or left alone? Thanks. - 73 and good DX de Mike, K6MKF, NCDXC Secretary > -Original Message- > From: elecraft-boun...@mailman.qth.net > On Behalf Of Keith Trinity WE6R > Sent: Thursday, December 26, 2019 15:25 > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] K3 - Power cable voltage drop > > Notes for all; > Check the K3 config menu item "ADC REF". If at 5.00 it is probably at > default. > (if at 4.00 a glitch occurred, probably during FW update, and will FUBAR the > internal metering. Set to 5.00 or read on). > (I check this during checkout, so if it has been in for Service, it should be OK). > > Higher accuracy of the K3 items like the internal Volt-Meter can be had if this is > set properly. > With a known external meter on Pin 2 to ground of the 15 pin ACCY connector; > Go into config menu ADC REF and set it. > > Also you can stick your probes into the Anderson connectors at the back of the > radio during full power TX to see the actual voltage to the radio. > (I have a digital LED meter connected with small wires to the Anderson supply > wire right at the back of the radio on my K3 test bench). > Keith WE6R > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Message > delivered to mike.flow...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Notes for all; Check the K3 config menu item "ADC REF". If at 5.00 it is probably at default. (if at 4.00 a glitch occurred, probably during FW update, and will FUBAR the internal metering. Set to 5.00 or read on). (I check this during checkout, so if it has been in for Service, it should be OK). Higher accuracy of the K3 items like the internal Volt-Meter can be had if this is set properly. With a known external meter on Pin 2 to ground of the 15 pin ACCY connector; Go into config menu ADC REF and set it. Also you can stick your probes into the Anderson connectors at the back of the radio during full power TX to see the actual voltage to the radio. (I have a digital LED meter connected with small wires to the Anderson supply wire right at the back of the radio on my K3 test bench). Keith WE6R __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Concur. -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Vic Rosenthal Sent: Tuesday, December 24, 2019 9:34 PM To: hawley, charles j jr Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop I have a Fluke DVM also. I gulped when I bought it some 30+ years ago, but it was a good decision. It’s like a Snap-On wrench. It just feels right and never let me down. Victor 4X6GP > On 25 Dec 2019, at 4:29, hawley, charles j jr wrote: > > I have a Fluke 87...for a couple of decades now. It does it all well. > > Chuck Jack Hawley > KE9UW > > Sent from my iPhone, cjack > >> On Dec 23, 2019, at 10:31 PM, Bob McGraw K4TAX wrote: >> >> A good, known accurate DVM is an asset to any station. Use it to determine >> if the others are accurate. There are several good brands available. A >> DVM that is not accurate is worse than no DVM at all. >> >> My choice of many years ago is my Fluke 77. After I tapped it with too >> much voltage, I sent it to Fluke for repair and calibration. I am confident >> when I make a measurement it is accurate without question. >> >> Bob, K4TAX >> >> >> Sent from my iPhone >> >>>> On Dec 23, 2019, at 2:12 PM, Buck wrote: >>> >>> The reliable place to measure the voltage at the K3x is using the supply >>> voltage display meter in the radio. I was surprised to find mine was >>> significantly low. I thought it was voltage drop but changing the supply >>> cable didn't make much difference. >>> >>> Turns out the Astron power supply was more than a volt low and the meter on >>> the supply had been cranked up to make it appear to be correct. I used two >>> separate VOMs to set the power supply and then adjusted the meter to make >>> it agree. >>> >>> Moral of the story: don't rely on the meter on the power supply and assume >>> a low reading at the radio is due solely to voltage drop. >>> >>> >>> >>> Buck, k4ia >>> Honor Roll >>> 8BDXCC >>> EasyWayHamBooks.com >>> >>>>> On 12/23/2019 2:26 PM, Phil Kane wrote: >>>>> On 12/22/2019 9:44 AM, Bob McGraw wrote: >>>>> I also added a dedicated ground between the ground screw on the >>>>> back of the radio to the ground screw on the power supply. >>>> That's for "bonding". Where do you pick up "ground" - at the >>>> radio, at the PS, or at some other point? >>>> 73 de K2ASP - Phil Kane >>>> Elecraft K2/100 s/n 5402 >>>> From a Clearing in the Silicon Forest Beaverton (Washington County) >>>> Oregon >>>> __ >>>> Elecraft mailing list >>>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>>> Help: http://mailman.qth.net/mmfaq.htm >>>> Post: mailto:Elecraft@mailman.qth.net This list hosted by: >>>> http://www.qsl.net Please help support this email list: >>>> http://www.qsl.net/donate.html Message delivered to >>>> radiok...@gmail.com >>> __ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net Please help support this >>> email list: http://www.qsl.net/donate.html Message delivered to >>> rmcg...@blomand.net >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net Please help support this >> email list: http://www.qsl.net/donate.html Message delivered to >> c-haw...@illinois.edu > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > k2vco@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to gthorn...@thorntonmostullaw.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I have a Fluke DVM also. I gulped when I bought it some 30+ years ago, but it was a good decision. It’s like a Snap-On wrench. It just feels right and never let me down. Victor 4X6GP > On 25 Dec 2019, at 4:29, hawley, charles j jr wrote: > > I have a Fluke 87...for a couple of decades now. It does it all well. > > Chuck Jack Hawley > KE9UW > > Sent from my iPhone, cjack > >> On Dec 23, 2019, at 10:31 PM, Bob McGraw K4TAX wrote: >> >> A good, known accurate DVM is an asset to any station. Use it to determine >> if the others are accurate. There are several good brands available. A >> DVM that is not accurate is worse than no DVM at all. >> >> My choice of many years ago is my Fluke 77. After I tapped it with too >> much voltage, I sent it to Fluke for repair and calibration. I am confident >> when I make a measurement it is accurate without question. >> >> Bob, K4TAX >> >> >> Sent from my iPhone >> On Dec 23, 2019, at 2:12 PM, Buck wrote: >>> >>> The reliable place to measure the voltage at the K3x is using the supply >>> voltage display meter in the radio. I was surprised to find mine was >>> significantly low. I thought it was voltage drop but changing the supply >>> cable didn't make much difference. >>> >>> Turns out the Astron power supply was more than a volt low and the meter on >>> the supply had been cranked up to make it appear to be correct. I used two >>> separate VOMs to set the power supply and then adjusted the meter to make >>> it agree. >>> >>> Moral of the story: don't rely on the meter on the power supply and assume >>> a low reading at the radio is due solely to voltage drop. >>> >>> >>> >>> Buck, k4ia >>> Honor Roll >>> 8BDXCC >>> EasyWayHamBooks.com >>> > On 12/23/2019 2:26 PM, Phil Kane wrote: > On 12/22/2019 9:44 AM, Bob McGraw wrote: > I also added a dedicated ground between the ground screw on the back of > the radio to the ground screw on the power supply. That's for "bonding". Where do you pick up "ground" - at the radio, at the PS, or at some other point? 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to radiok...@gmail.com >>> __ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to rmcg...@blomand.net >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to c-haw...@illinois.edu > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to k2vco@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Yes true. However seeing they way some hams configure their stations, building or modifying and implementing a power supply with voltage sensing, is of serious questionable nature. Likewise, in conditions where power supplies are buried under the desk. One needs to see the volt meter when the supply is first turned on to assure the voltage is correct. And that should be done before the radio is turned on. Oh I know about crowbar circuits, but if that $2.50 part fails it will likely take out a $3000 radio. This just isn't smart. Having worked with equipment that was supplied with 35 ft or 50 ft power cables for loads of 20A to 30A at + & - 18 volts, I understand just a wee bit about voltage sensing circuits and what makes them oscillate. Just err on the safe side. And for ham radio, it likely is not necessary to have or implement remote voltage sensing. Wire and connectors are cheap. Use a shorter length of wire or larger gauge wire. There's no likely component failure with this approach. 73 Bob, K4TAX On 12/24/2019 8:25 PM, K9MA wrote: Typically, there are small resistors at the power supply between the output and sense terminals to prevent the voltage from rising if a sense wire opens up. 73, Scott K9MA -- Scott Ellington --- via iPad On Dec 24, 2019, at 5:39 PM, Bob McGraw K4TAX wrote: Yes, but one screw-up on the remote sensing system and it will take advantage of the voltage overhead on the pass transistors and likely wipe out every piece of equipment. I strongly do not advise it. And you make a valid point for NOT using remote sensing. 73 Bob, K4TAX On 12/24/2019 3:22 PM, Jim Rhodes wrote: I have thought about doing that. Just requires a 2 wire hookup with small gauge wire. But I run all of my small items like the remoterig box, LP-pan box, VHF/UHF rig and so forth off of the main supply and if I have a larger than anticipated voltage drop on rig power cable the voltage on the other tings could go fairly high. The power supply is a HB thing with at least a 50 amp capacity and plenty of voltage overhead before pass transistors. (Used to run 2 HF rigs before downsizing.) On Tue, Dec 24, 2019 at 2:25 PM Rose wrote: First, it would require some basic technical skill ... (;-) 73 K0PP On Tue, Dec 24, 2019, 13:20 Karin Johnson wrote: Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to elecraftcov...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to jimk...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k...@sdellington.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I have a Fluke 87...for a couple of decades now. It does it all well. Chuck Jack Hawley KE9UW Sent from my iPhone, cjack > On Dec 23, 2019, at 10:31 PM, Bob McGraw K4TAX wrote: > > A good, known accurate DVM is an asset to any station. Use it to determine > if the others are accurate. There are several good brands available. A DVM > that is not accurate is worse than no DVM at all. > > My choice of many years ago is my Fluke 77. After I tapped it with too much > voltage, I sent it to Fluke for repair and calibration. I am confident when > I make a measurement it is accurate without question. > > Bob, K4TAX > > > Sent from my iPhone > >> On Dec 23, 2019, at 2:12 PM, Buck wrote: >> >> The reliable place to measure the voltage at the K3x is using the supply >> voltage display meter in the radio. I was surprised to find mine was >> significantly low. I thought it was voltage drop but changing the supply >> cable didn't make much difference. >> >> Turns out the Astron power supply was more than a volt low and the meter on >> the supply had been cranked up to make it appear to be correct. I used two >> separate VOMs to set the power supply and then adjusted the meter to make it >> agree. >> >> Moral of the story: don't rely on the meter on the power supply and assume a >> low reading at the radio is due solely to voltage drop. >> >> >> >> Buck, k4ia >> Honor Roll >> 8BDXCC >> EasyWayHamBooks.com >> On 12/23/2019 2:26 PM, Phil Kane wrote: On 12/22/2019 9:44 AM, Bob McGraw wrote: I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. >>> That's for "bonding". Where do you pick up "ground" - at the radio, at >>> the PS, or at some other point? >>> 73 de K2ASP - Phil Kane >>> Elecraft K2/100 s/n 5402 >>> From a Clearing in the Silicon Forest >>> Beaverton (Washington County) Oregon >>> __ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to radiok...@gmail.com >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to rmcg...@blomand.net > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to c-haw...@illinois.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Typically, there are small resistors at the power supply between the output and sense terminals to prevent the voltage from rising if a sense wire opens up. 73, Scott K9MA -- Scott Ellington --- via iPad > On Dec 24, 2019, at 5:39 PM, Bob McGraw K4TAX wrote: > > Yes, but one screw-up on the remote sensing system and it will take > advantage of the voltage overhead on the pass transistors and likely wipe out > every piece of equipment. I strongly do not advise it. And you make a > valid point for NOT using remote sensing. > > 73 > > Bob, K4TAX > >> On 12/24/2019 3:22 PM, Jim Rhodes wrote: >> I have thought about doing that. Just requires a 2 wire hookup with small >> gauge wire. But I run all of my small items like the remoterig box, LP-pan >> box, VHF/UHF rig and so forth off of the main supply and if I have a larger >> than anticipated voltage drop on rig power cable the voltage on the other >> tings could go fairly high. The power supply is a HB thing with at least a >> 50 amp capacity and plenty of voltage overhead before pass transistors. >> (Used to run 2 HF rigs before downsizing.) >> >> >>> On Tue, Dec 24, 2019 at 2:25 PM Rose wrote: >>> >>> First, it would require some basic technical skill ... (;-) >>> >>> 73 >>> >>> K0PP >>> >>> On Tue, Dec 24, 2019, 13:20 Karin Johnson >>> wrote: >>> Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to elecraftcov...@gmail.com >>> __ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> Message delivered to jimk...@gmail.com >>> >> > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to k...@sdellington.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Yes, but one screw-up on the remote sensing system and it will take advantage of the voltage overhead on the pass transistors and likely wipe out every piece of equipment. I strongly do not advise it. And you make a valid point for NOT using remote sensing. 73 Bob, K4TAX On 12/24/2019 3:22 PM, Jim Rhodes wrote: I have thought about doing that. Just requires a 2 wire hookup with small gauge wire. But I run all of my small items like the remoterig box, LP-pan box, VHF/UHF rig and so forth off of the main supply and if I have a larger than anticipated voltage drop on rig power cable the voltage on the other tings could go fairly high. The power supply is a HB thing with at least a 50 amp capacity and plenty of voltage overhead before pass transistors. (Used to run 2 HF rigs before downsizing.) On Tue, Dec 24, 2019 at 2:25 PM Rose wrote: First, it would require some basic technical skill ... (;-) 73 K0PP On Tue, Dec 24, 2019, 13:20 Karin Johnson wrote: Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to elecraftcov...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to jimk...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
With the Astron supplies, the 723 regulator does have provision for remote sensing. And with a bit of work and some extra wiring and components one can have remote sensing. I would suggest NOT doing so as remote sensing become "inputs" to the 723 regulator chip and any noise or RF on the remote sensing lines can be very problematic. Proper filtering and time constants will be required to prevent oscillations. My suggestion is to use good quality #10 AWG wire, such as auto primary wire fitted with correct terminals on the ends. Be sure to correctly crimp and solder as needed. Suggested length is something less than 10 ft. Also be sure to have a dedicated ground between the ground screw on the back of the radio to the ground on the power supply. In the end, if you desire to have remote sensing, purchase a suitable supply that provides remote sensing. Life will be much easier. 73 Bob, K4TAX On 12/24/2019 2:20 PM, Karin Johnson wrote: Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to rmcg...@blomand.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
There can be stability issues with remote sensing. Also RF susceptibility. Take care! 73, Scott K9MA -- Scott Ellington --- via iPad > On Dec 24, 2019, at 4:03 PM, Don Wilhelm wrote: > > That would be a neat thing to do, but DO NOT do that on a power supply that > is connected to anything other than the rig you are sensing from. > > The voltage on other devices connected to the power supply will increase when > you transmit on the rig to which the sense wires are connected. > > Use a separate power supply for accessories. > > If you need to use the same supply, you can adjust the voltage upward - the > SS30 sold by Elecraft already has an output voltage of 14.1 volts. > Still use a separate power cable to the transceiver and another cable to any > distribution box that you use for accessories for best results (lowest > voltage drop when transmitting). > > 73, > Don W3FPR > >> On 12/24/2019 4:23 PM, K4HYJ via Elecraft wrote: >> I do use voltage sensing at the rear of the radio. Astron supplies can be >> modified easily to do this - they already have sense wires tied to the >> voltage output terminals. Basically you disconnect them there and run leads >> (keep em short) to the radio. On transmit, my K3s drops less than 1/10 a >> volt. >> There are a few write ups floating around on how to do this. I installed a >> switch (make before break type) on my RS-50M so I can return to "normal" >> sensing. ***WARNING*** If the external sense wires are not connected to >> anything the crowbar circuit will fire!!! > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to k...@sdellington.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
That would be a neat thing to do, but DO NOT do that on a power supply that is connected to anything other than the rig you are sensing from. The voltage on other devices connected to the power supply will increase when you transmit on the rig to which the sense wires are connected. Use a separate power supply for accessories. If you need to use the same supply, you can adjust the voltage upward - the SS30 sold by Elecraft already has an output voltage of 14.1 volts. Still use a separate power cable to the transceiver and another cable to any distribution box that you use for accessories for best results (lowest voltage drop when transmitting). 73, Don W3FPR On 12/24/2019 4:23 PM, K4HYJ via Elecraft wrote: I do use voltage sensing at the rear of the radio. Astron supplies can be modified easily to do this - they already have sense wires tied to the voltage output terminals. Basically you disconnect them there and run leads (keep em short) to the radio. On transmit, my K3s drops less than 1/10 a volt. There are a few write ups floating around on how to do this. I installed a switch (make before break type) on my RS-50M so I can return to "normal" sensing. ***WARNING*** If the external sense wires are not connected to anything the crowbar circuit will fire!!! __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I do use voltage sensing at the rear of the radio. Astron supplies can be modified easily to do this - they already have sense wires tied to the voltage output terminals. Basically you disconnect them there and run leads (keep em short) to the radio. On transmit, my K3s drops less than 1/10 a volt. There are a few write ups floating around on how to do this. I installed a switch (make before break type) on my RS-50M so I can return to "normal" sensing. ***WARNING*** If the external sense wires are not connected to anything the crowbar circuit will fire!!! Hank K4HYJ -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Karin Johnson Sent: Tuesday, December 24, 2019 3:20 PM To: elecraft@mailman.qth.net Subject: [Elecraft] K3 - Power cable voltage drop Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to h...@optilink.us __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I have thought about doing that. Just requires a 2 wire hookup with small gauge wire. But I run all of my small items like the remoterig box, LP-pan box, VHF/UHF rig and so forth off of the main supply and if I have a larger than anticipated voltage drop on rig power cable the voltage on the other tings could go fairly high. The power supply is a HB thing with at least a 50 amp capacity and plenty of voltage overhead before pass transistors. (Used to run 2 HF rigs before downsizing.) On Tue, Dec 24, 2019 at 2:25 PM Rose wrote: > First, it would require some basic technical skill ... (;-) > > 73 > > K0PP > > On Tue, Dec 24, 2019, 13:20 Karin Johnson > wrote: > > > Why hasn't anyone used remote sensing at the radio voltage input? > > As far as I know all of the Astron supplies don't have external sense > > wiring. Many so called professional grade high current supplies provide > > For external connection of the voltage sense back to the regulator chip. > > I've toyed with this idea a bit but haven't had the time dig in to the > > Astron supply I have. If this were implemented then one could maintain > > 13.8 volts or whatever you desired at the radio power supply inputs, > > Regardless of the current draw. > > > > Karin Anne Johnson K3UU > > > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to elecraftcov...@gmail.com > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to jimk...@gmail.com > -- Jim K0XU j...@rhodesend.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
First, it would require some basic technical skill ... (;-) 73 K0PP On Tue, Dec 24, 2019, 13:20 Karin Johnson wrote: > Why hasn't anyone used remote sensing at the radio voltage input? > As far as I know all of the Astron supplies don't have external sense > wiring. Many so called professional grade high current supplies provide > For external connection of the voltage sense back to the regulator chip. > I've toyed with this idea a bit but haven't had the time dig in to the > Astron supply I have. If this were implemented then one could maintain > 13.8 volts or whatever you desired at the radio power supply inputs, > Regardless of the current draw. > > Karin Anne Johnson K3UU > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to elecraftcov...@gmail.com > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] K3 - Power cable voltage drop
Why hasn't anyone used remote sensing at the radio voltage input? As far as I know all of the Astron supplies don't have external sense wiring. Many so called professional grade high current supplies provide For external connection of the voltage sense back to the regulator chip. I've toyed with this idea a bit but haven't had the time dig in to the Astron supply I have. If this were implemented then one could maintain 13.8 volts or whatever you desired at the radio power supply inputs, Regardless of the current draw. Karin Anne Johnson K3UU __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
A good, known accurate DVM is an asset to any station. Use it to determine if the others are accurate. There are several good brands available. A DVM that is not accurate is worse than no DVM at all. My choice of many years ago is my Fluke 77. After I tapped it with too much voltage, I sent it to Fluke for repair and calibration. I am confident when I make a measurement it is accurate without question. Bob, K4TAX Sent from my iPhone > On Dec 23, 2019, at 2:12 PM, Buck wrote: > > The reliable place to measure the voltage at the K3x is using the supply > voltage display meter in the radio. I was surprised to find mine was > significantly low. I thought it was voltage drop but changing the supply > cable didn't make much difference. > > Turns out the Astron power supply was more than a volt low and the meter on > the supply had been cranked up to make it appear to be correct. I used two > separate VOMs to set the power supply and then adjusted the meter to make it > agree. > > Moral of the story: don't rely on the meter on the power supply and assume a > low reading at the radio is due solely to voltage drop. > > > > Buck, k4ia > Honor Roll > 8BDXCC > EasyWayHamBooks.com > >> On 12/23/2019 2:26 PM, Phil Kane wrote: >>> On 12/22/2019 9:44 AM, Bob McGraw wrote: >>> I also added a dedicated ground between the ground screw on the back of >>> the radio to the ground screw on the power supply. >> That's for "bonding". Where do you pick up "ground" - at the radio, at >> the PS, or at some other point? >> 73 de K2ASP - Phil Kane >> Elecraft K2/100 s/n 5402 >> From a Clearing in the Silicon Forest >> Beaverton (Washington County) Oregon >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to radiok...@gmail.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to rmcg...@blomand.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I do not use a “ground” at the station. I don’t find or see that it’s needed. My station has a 4 wire #10 service from the breaker panel to the operating position. The breakers are single 20A units. This gives me 240V for the amp and a duplex off of each leg. Thus I maintain a common neutral and common ground to the breaker panel. Grounding for lightning protection is done outside of the house and that system is bonded back to the AC Mains ground rod below the service entrance. Bob, K4TAX Sent from my iPhone > On Dec 23, 2019, at 1:44 PM, Phil Kane wrote: > > On 12/22/2019 9:44 AM, Bob McGraw wrote: > >> I also added a dedicated ground between the ground screw on the back of >> the radio to the ground screw on the power supply. > > That's for "bonding". Where do you pick up "ground" - at the radio, at > the PS, or at some other point? > > 73 de K2ASP - Phil Kane > Elecraft K2/100 s/n 5402 > > From a Clearing in the Silicon Forest > Beaverton (Washington County) Oregon > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to rmcg...@blomand.net > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
The reliable place to measure the voltage at the K3x is using the supply voltage display meter in the radio. I was surprised to find mine was significantly low. I thought it was voltage drop but changing the supply cable didn't make much difference. Turns out the Astron power supply was more than a volt low and the meter on the supply had been cranked up to make it appear to be correct. I used two separate VOMs to set the power supply and then adjusted the meter to make it agree. Moral of the story: don't rely on the meter on the power supply and assume a low reading at the radio is due solely to voltage drop. Buck, k4ia Honor Roll 8BDXCC EasyWayHamBooks.com On 12/23/2019 2:26 PM, Phil Kane wrote: On 12/22/2019 9:44 AM, Bob McGraw wrote: I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. That's for "bonding". Where do you pick up "ground" - at the radio, at the PS, or at some other point? 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to radiok...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
On 12/22/2019 9:44 AM, Bob McGraw wrote: > I also added a dedicated ground between the ground screw on the back of > the radio to the ground screw on the power supply. That's for "bonding". Where do you pick up "ground" - at the radio, at the PS, or at some other point? 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
On 12/22/2019 9:44 AM, Bob McGraw wrote: Rid your station of the DC power strip. It will cause problems. More connections in the path will be more DC voltage drip. The radios should be connected direct to the power supply. Yes and no. My station has direct short runs from a 100Ah Bioenne LiFePO4 battery to my two K3s. The radio very close to the battery is #10; the longer run (about five ft) to the radio on the other side of the desk is two #10s in parallel. This battery is used because it's operating voltage remains well about 13VDC throughout its discharge curve (as opposed to the SLA, which is closer to 11.5VDC under load). The difference results in lower IMD. The other 12V gear (and LED strips for task lighting) runs from a 100Ah 12V SLA battery through a DC power strip. All the gear is bonded together. Both batteries are float-charged by spare Thinkpad power supplies with Genasun charge regulators. The power strips are fine for low current drain devices, but, as Bob notes, not for the radios. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I used to run my K3S with an auto turn on Rigrunner which I liked very much, convenient. But the voltage drop was concerning. I go direct now to the rig. Chuck Jack Hawley KE9UW Sent from my iPhone, cjack > On Dec 22, 2019, at 10:21 AM, Don Wilhelm wrote: > > Tony, > > While those figures with the 10 gauge wire are good, they would be better if > you ran the K3 power directly from the power supply rather than from the > power distribution strip. > > Each connection will have some voltage drop, so in addition to increasing the > wiring gauge, reducing the connection points will help just as much. > > 73 Merry Christmas, or Happy Hanukkah whichever you choose to celebrate. > Don W3FPR > >> On 12/22/2019 10:47 AM, N2TK via Elecraft wrote: >> I have been using an Astron SS-30M power supply for several years to feed >> two K3's. >> I use 12ga wire from the power supply to an MFJ-4012 power strip. From the >> power strip I use 12ga wire to each K3. Total length from power supply to a >> K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's were >> tested one at a time. The power supply voltage went from 14.38 to 14.30 at >> 100W. >> Both K3's read the same on the K3's internal voltmeter - 14.1V in receive >> and 12.7V at 100W setting on the K3's. The P3 read 107W out. >> Changed the cable to 10ga wire direct from the power supply to each K3. >> Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. >> Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' of >> 10ga wire. >> P3 output was now 114W. > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to c-haw...@illinois.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
I still connect all of the equipment which used walwarts to my power supply. I made provisions to have many many DC connections, as described below, to my supplies. All of my DC power leads have the correct size crimp ring terminal for the application. Never use stranded wire around a screw. Thus many problems solved. I know the DC distribution strips look cool with their LEDs and fuses and connectors, and are very easy to use for convenience. But I find just like AC strips, are a source of many problems. I've found many of the AC strips which have a poor 3rd wire connection. They are a matter of convenience and not of reliable functionality. As to the Astron SS-30M, I have 3 of those. They are great. I did find the provided DC connections where the wires are inserted into the blocks and secured with a screw from the side would not accommodate the 4 needs for DC at my station.Therefore, I took two pieces of 2" x 10-32 brass machine screw, cut off the head, filed a small flat spot on one side at the end to make it slightly D shaped. Inserted that end into the DC connector and tightened the set screw against the flat spot. Then added as needed the brass nuts, flat washers and lock washers, secured finally by another brass nut. This in effect gives me very adequate terminal length to attach as many DC power leads with suitable ring terminals as needed. DC resistance has therefore been minimized. The 10 ga wire is a good addition for radio power needs. I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. 73 Bob, K4TAX __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
In my current station layout the rack-mounted Astron-50M is separated from the radio shelf, so I need a 15-foot run of cable. The Astron runs 14.2 vdc. I have 13.69 v at the main power strip (handles 10ga wiring). The primary dc power cable is No. 6 welding cable (more flexible than std No. 6) so I have a BUSS30 fuse at the main power strip. The Astron is capable of 50 amps if the main cable were to short (cable is rated for a over 200A for welding). I use the std power cord that came with my K3/10 and see 13.3v displayed by the K3 in transmit with 10w RF output. The K3/10 does not draw a lot of current. I drive a KXPA100 which has 5-foot Elecraft power cable (looks like No.12). I get 100w on all bands with about 5w drive (only 6m requires 8w drive for 80w output). I have not measured the voltage at the power-pole connector when in transmit but should be approx 13.5v based on current draw of 20 A. I run several high power solid-state amplifiers that draw up to 50A at 50v so paying attention to dc voltage drop in dc wiring is quite important. 73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: dubus...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Bob, The power strip is gone for the K3's. Now direct connections from the PS to each K3. The power strip is good for replacing the walwarts. N2TK, Tony -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Bob McGraw Sent: Sunday, December 22, 2019 12:45 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop Rid your station of the DC power strip. It will cause problems. More connections in the path will be more DC voltage drip. The radios should be connected direct to the power supply. As to the Astron SS-30M, I have 3 of those. They are great. I did find the provided DC connections where the wires are inserted into the blocks and secured with a screw from the side would not accommodate the 4 needs for DC at my station.Therefore, I took two pieces of 2" x 10-32 brass machine screw, cut off the head, filed a small flat spot on one side at the end to make it slightly D shaped. Inserted that end into the DC connector and tightened the set screw against the flat spot. Then added as needed the brass nuts, flat washers and lock washers, secured finally by another brass nut. This in effect gives me very adequate terminal length to attach as many DC power leads with suitable ring terminals as needed. DC resistance has therefore been minimized. The 10 ga wire is a good addition for radio power needs. I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. 73 Bob, K4TAX 12/22/2019 10:47 AM, N2TK via Elecraft wrote: > I have been using an Astron SS-30M power supply for several years to > feed two K3's. > I use 12ga wire from the power supply to an MFJ-4012 power strip. From > the power strip I use 12ga wire to each K3. Total length from power > supply to a > K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's > were tested one at a time. The power supply voltage went from 14.38 to > 14.30 at 100W. > Both K3's read the same on the K3's internal voltmeter - 14.1V in > receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. > Changed the cable to 10ga wire direct from the power supply to each K3. > Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. > Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' > of 10ga wire. > P3 output was now 114W. > I never transmit with both K3's at the same time. > Just a data point. > 73 and Merry Christmas > N2TK, Tony > > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Message delivered to > rmcg...@blomand.net > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to tony@verizon.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Hi Don, With the 10ga wire the power distribution strip is not used. There are two runs of 7' each direct from the power supply to a K3. The run is 7' because I have the power supply with the rest of my supplies, router, etc. all mounted underneath my desk to the side to keep the desktop clean. I don't hink 0.6V drop is too much to be concerned with. The amps are in the basement. In the process of adding Green Heron Everywhere wireless remotes to eliminate the manual switches too. 73 and merry Christmas N2TK, Tony -Original Message- From: Don Wilhelm Sent: Sunday, December 22, 2019 11:21 AM To: tony@verizon.net; elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop Tony, While those figures with the 10 gauge wire are good, they would be better if you ran the K3 power directly from the power supply rather than from the power distribution strip. Each connection will have some voltage drop, so in addition to increasing the wiring gauge, reducing the connection points will help just as much. 73 Merry Christmas, or Happy Hanukkah whichever you choose to celebrate. Don W3FPR On 12/22/2019 10:47 AM, N2TK via Elecraft wrote: > I have been using an Astron SS-30M power supply for several years to > feed two K3's. > I use 12ga wire from the power supply to an MFJ-4012 power strip. From > the power strip I use 12ga wire to each K3. Total length from power > supply to a > K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's > were tested one at a time. The power supply voltage went from 14.38 to > 14.30 at 100W. > Both K3's read the same on the K3's internal voltmeter - 14.1V in > receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. > Changed the cable to 10ga wire direct from the power supply to each K3. > Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. > Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' > of 10ga wire. > P3 output was now 114W. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Rid your station of the DC power strip. It will cause problems. More connections in the path will be more DC voltage drip. The radios should be connected direct to the power supply. As to the Astron SS-30M, I have 3 of those. They are great. I did find the provided DC connections where the wires are inserted into the blocks and secured with a screw from the side would not accommodate the 4 needs for DC at my station. Therefore, I took two pieces of 2" x 10-32 brass machine screw, cut off the head, filed a small flat spot on one side at the end to make it slightly D shaped. Inserted that end into the DC connector and tightened the set screw against the flat spot. Then added as needed the brass nuts, flat washers and lock washers, secured finally by another brass nut. This in effect gives me very adequate terminal length to attach as many DC power leads with suitable ring terminals as needed. DC resistance has therefore been minimized. The 10 ga wire is a good addition for radio power needs. I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. 73 Bob, K4TAX 12/22/2019 10:47 AM, N2TK via Elecraft wrote: I have been using an Astron SS-30M power supply for several years to feed two K3's. I use 12ga wire from the power supply to an MFJ-4012 power strip. From the power strip I use 12ga wire to each K3. Total length from power supply to a K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's were tested one at a time. The power supply voltage went from 14.38 to 14.30 at 100W. Both K3's read the same on the K3's internal voltmeter - 14.1V in receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. Changed the cable to 10ga wire direct from the power supply to each K3. Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' of 10ga wire. P3 output was now 114W. I never transmit with both K3's at the same time. Just a data point. 73 and Merry Christmas N2TK, Tony __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to rmcg...@blomand.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - Power cable voltage drop
Tony, While those figures with the 10 gauge wire are good, they would be better if you ran the K3 power directly from the power supply rather than from the power distribution strip. Each connection will have some voltage drop, so in addition to increasing the wiring gauge, reducing the connection points will help just as much. 73 Merry Christmas, or Happy Hanukkah whichever you choose to celebrate. Don W3FPR On 12/22/2019 10:47 AM, N2TK via Elecraft wrote: I have been using an Astron SS-30M power supply for several years to feed two K3's. I use 12ga wire from the power supply to an MFJ-4012 power strip. From the power strip I use 12ga wire to each K3. Total length from power supply to a K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's were tested one at a time. The power supply voltage went from 14.38 to 14.30 at 100W. Both K3's read the same on the K3's internal voltmeter - 14.1V in receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. Changed the cable to 10ga wire direct from the power supply to each K3. Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' of 10ga wire. P3 output was now 114W. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] K3 - Power cable voltage drop
I have been using an Astron SS-30M power supply for several years to feed two K3's. I use 12ga wire from the power supply to an MFJ-4012 power strip. From the power strip I use 12ga wire to each K3. Total length from power supply to a K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's were tested one at a time. The power supply voltage went from 14.38 to 14.30 at 100W. Both K3's read the same on the K3's internal voltmeter - 14.1V in receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. Changed the cable to 10ga wire direct from the power supply to each K3. Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' of 10ga wire. P3 output was now 114W. I never transmit with both K3's at the same time. Just a data point. 73 and Merry Christmas N2TK, Tony __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3: Power cable question
Glad you raised that point, Brian. In my Sunday school classes I ask the question: what does the fuse protect? It's a revelation to all when I give the right answer. On our 240V distribution system, a melted cable can lead to a severe shock hazard and I'm guessing that in the 110V centre-tapped system since the shock hazard is so much less, the next major hazard is fire, so, I've often thought that we are protecting against 2 hazards, each with a different emphasis in each case. In a 14V dc distribution system there is no real shock hazard (SELV), so the remaining hazard has to be fire, so, a slow fuse is not a problem, since heating effect in the wiring is so much slower. Anyone care to comment/add? David On Jun 16, 2008, at 9:59 PM, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: A regular fuse should blow at 2.6 x the rating within 30s, in other words very slowly. It's only a short circuit that will normally blow a new fuse. Have not seen any data on old fuses which might get metal fatigue. There are faster fuses, but the fastest are rf transistors - on three legs anyway... Most people don't know that the purpose of a fuse or circuit breaker is to protect the power distribution wiring, not the electronic component itself. Wire will carry a surge without too much temperature rise. The idea is that the fuse will blow or the breaker open before there is any chance of damage to the wire. This means that a fuse or breaker cannot protect your active devices. If you want that level of protection you need something like a power supply with fold-back current limiting. Brian Lloyd ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3: Power cable question
--- David Cutter [EMAIL PROTECTED] wrote: Glad you raised that point, Brian. In my Sunday school classes I ask the question: what does the fuse protect? It's a revelation to all when I give the right answer. On our 240V distribution system, a melted cable can lead to a severe shock hazard and I'm guessing that in the 110V centre-tapped system since the shock hazard is so much less, the next major hazard is fire, so, I've often You are right David. 110 VAC is much safer than 240V, it can just barely kill you. Cookie, K5EWJ Willis 'Cookie' Cooke K5EWJ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3: Power cable question
Hi Ron, Thanks for the analysis. You pointed out several things I was unaware of related to these types of fuses. Nice to learn something new! I'm in the process of redoing the power distribution in my shack, so will take this info into account. Fortunately, it's been a while since I've blown any fuse. Cheers, Julius Julius Fazekas N2WN Tennessee Contest Group TnQP http://www.tnqp.org/ Elecraft K2/100 #3311 Elecraft K2/100 #4455 Elecraft K3/100 #366 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3: Power cable question
On Jun 16, 2008, at 9:59 PM, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: A regular fuse should blow at 2.6 x the rating within 30s, in other words very slowly. It's only a short circuit that will normally blow a new fuse. Have not seen any data on old fuses which might get metal fatigue. There are faster fuses, but the fastest are rf transistors - on three legs anyway... Most people don't know that the purpose of a fuse or circuit breaker is to protect the power distribution wiring, not the electronic component itself. Wire will carry a surge without too much temperature rise. The idea is that the fuse will blow or the breaker open before there is any chance of damage to the wire. This means that a fuse or breaker cannot protect your active devices. If you want that level of protection you need something like a power supply with fold-back current limiting. Brian Lloyd Granite Bay Montessori School 9330 Sierra College Bl brian AT gbmontessori DOT com Roseville, CA 95661 +1.916.367.2131 (voice)+1.791.912.8170 (fax) PGP key ID: 12095C52A32A1B6C PGP key fingerprint: 3B1D BA11 4913 3254 B6E0 CC09 1209 5C52 A32A 1B6C ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3: Power cable question
Ron, I've been using my K2 cable with my K3, including contests, without an issue. Considering what the KPA100 will do with my 160M setup, in the way of drawing current, I think there is enough wiggle room not to worry too much. The K3 barely gets warm when I run :o) 73, Julius Julius Fazekas N2WN Tennessee Contest Group TnQP http://www.tnqp.org/ Elecraft K2/100 #3311 Elecraft K2/100 #4455 Elecraft K3/100 #366 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3: Power cable question
Hi Julius: I measure just over 20 Amps under some bands and conditions running the K3 at 100 watts. Like the K2, I suspect the current draw varies a bit depending upon the rig, the actual parameters of some of the transistors, etc. That's normal, according to the K3 specs, which rate the current demand at 17-22 amps at 100 watts in transmit IMX fuses have a nasty habit of suddenly opening after being cycled a number of times near their rated limit, even the 'slo-blo' type that are supposed to offer a little resistance against sudden failure when their current limit is reached will sometimes open unexpectedly. I've seen fuses operating near their current limits develop cracks so they act like thermal switches, causing power to go off suddenly then, after a few seconds (while the fuse cools) suddenly come back on, then switch off again as soon as a higher current is drawn such as for transmitting. Eventually they fail completely, but in the meantime the symptoms can be pretty confusing. As a matter of practice I try to allow significant headroom between the rating of any fuses and the actual current draw, and I always have spare fuses on hand since they can and do fail over time, even if not subjected to excessive current. Ron AC7AC -Original Message- Ron, I've been using my K2 cable with my K3, including contests, without an issue. Considering what the KPA100 will do with my 160M setup, in the way of drawing current, I think there is enough wiggle room not to worry too much. The K3 barely gets warm when I run :o) 73, Julius ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: RE: [Elecraft] K3: Power cable question
A regular fuse should blow at 2.6 x the rating within 30s, in other words very slowly. It's only a short circuit that will normally blow a new fuse. Have not seen any data on old fuses which might get metal fatigue. There are faster fuses, but the fastest are rf transistors - on three legs anyway... David G3UNA From: Ron D'Eau Claire [EMAIL PROTECTED] Date: 2008/06/16 Mon PM 06:52:16 BST To: 'Elecraft Discussion List' elecraft@mailman.qth.net Subject: RE: [Elecraft] K3: Power cable question Hi Julius: I measure just over 20 Amps under some bands and conditions running the K3 at 100 watts. Like the K2, I suspect the current draw varies a bit depending upon the rig, the actual parameters of some of the transistors, etc. That's normal, according to the K3 specs, which rate the current demand at 17-22 amps at 100 watts in transmit IMX fuses have a nasty habit of suddenly opening after being cycled a number of times near their rated limit, even the 'slo-blo' type that are supposed to offer a little resistance against sudden failure when their current limit is reached will sometimes open unexpectedly. I've seen fuses operating near their current limits develop cracks so they act like thermal switches, causing power to go off suddenly then, after a few seconds (while the fuse cools) suddenly come back on, then switch off again as soon as a higher current is drawn such as for transmitting. Eventually they fail completely, but in the meantime the symptoms can be pretty confusing. As a matter of practice I try to allow significant headroom between the rating of any fuses and the actual current draw, and I always have spare fuses on hand since they can and do fail over time, even if not subjected to excessive current. Ron AC7AC -Original Message- Ron, I've been using my K2 cable with my K3, including contests, without an issue. Considering what the KPA100 will do with my 160M setup, in the way of drawing current, I think there is enough wiggle room not to worry too much. The K3 barely gets warm when I run :o) 73, Julius ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com - Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3: Power cable question
I haven't been able to locate this information in the documentation, so perhaps a kind soul could oblige? In anticipation of a K3/100 kit's arrival, I would like to know the length of power cord supplied and also whether the K2/100 power cable is interchangeable with the K3/100 (i.e. do the Andersons have the same orientation on K2 and K3)? Many thanks. DaveL G3TJP ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3: Power cable question
...whether the K2/100 power cable is interchangeable with the K3/100 (i.e. do the Andersons have the same orientation on K2 and K3)? Yes, they have the same orientation. I initially ran my K3 with my K2/100 cable. 73, Lyle KK7P ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3: Power cable question
Me too, but I realized that the K3 draws somewhat more current than the K2/100. Depending upon the band antenna, etc., the total current can exceed the rating of the rating of the 20-amp fuse in the K2/100 power cord. Ron AC7AC -Original Message- ...whether the K2/100 power cable is interchangeable with the K3/100 (i.e. do the Andersons have the same orientation on K2 and K3)? Yes, they have the same orientation. I initially ran my K3 with my K2/100 cable. 73, Lyle KK7P ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 power cable
Does the K3 come with the Anderson power poles already installed or at least in the kit? Tnx Tom CX7TT ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3 power cable
Hi The K3 has a PowerPole connector on the back of the radio and includes a kit to build up a 5 ft cable to plug into the radio. The power supply end is not supplied so you will need to connect the bare wires to your power supply or supply your own connector for your power supply. The cable kit includes 5 ft of #12 red/black zip cord, a set of red and black PowerPole connectors with terminal pins and instructions. The instructions recommend soldering the pins. Don Brown KD5NDB Date: Mon, 17 Mar 2008 19:37:47 +0400 From: [EMAIL PROTECTED] To: elecraft@mailman.qth.net Subject: [Elecraft] K3 power cable Does the K3 come with the Anderson power poles already installed or at least in the kit? Tnx Tom CX7TT ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
Tom, You will have to heat up the soldering iron for this one. They give you the connectors and cable...no fuses or fuse holders. You will have to crimp and solder. Lee K0WA In our day and age it seems that Common Sense is in short supply. If you don't have any Common Sense - get some Common Sense and use it. If you can't find any Common Sense, ask for help from somebody who has some Common Sense. Is Common Sense divine? ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
The connector was *not* installed on the cable in my K3 kit. 73, Ken K3IU [EMAIL PROTECTED] wrote: Does the K3 come with the Anderson power poles already installed or at least in the kit? Tnx Tom CX7TT ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
Others have given you the answer you were searching for, but I'll just chime in to say that during my K3 wait (June till February), I made a cable of 10 ga. zip, with an in-line fuse holder and PowerPoles on each end. I have a West Mountain Radio crimper available, so I crimped then soldered each terminal. The Elecraft power cable kit is still in its bag, waiting for another project. [EMAIL PROTECTED] wrote: Does the K3 come with the Anderson power poles already installed or at least in the kit? 73, Mike KW1ND ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] K3 power cable
Hey Guys, Tnx for the quick response...I have no problem with soldering as I did build a K2 a few years ago...My just delivered K3 is sitting at a friend's house in FL and I will be there this Friday evening. My friend does not use power poles so wanted to know if I would be able to set up and play with my new 'toy' during the weekend...Hooray...seems that I will; leave Monday nite for CX land and so will have it on the air by end of week...at least into vertical dipole or such. Tnx for all the positive comments and c u on the air with #250. 73 Tom ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
You either crimp or Solder - not both 73 de M0XDF, K3 #174 -- Sometimes I think we're alone in the universe, and sometimes I think we're not. In either case, the idea is quite staggering. -Arthur C Clarke, science fiction writer (1917- ) On 17 Mar 2008, at 15:50, Lee Buller wrote: Tom, You will have to heat up the soldering iron for this one. They give you the connectors and cable...no fuses or fuse holders. You will have to crimp and solder. Lee K0WA In our day and age it seems that Common Sense is in short supply. If you don't have any Common Sense - get some Common Sense and use it. If you can't find any Common Sense, ask for help from somebody who has some Common Sense. Is Common Sense divine? ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
You either crimp or Solder - not both While it may be easy to prove that doing both is redundant, I see no reason why one *can't* do both, provided you crimp before soldering. I find it rather odd to make such a firm distinction. If I'm planning ahead and remember to bring the crimpers home from work, I'll typically just crimp. Otherwise, I just solder. Sometimes, though, I'll get picky and do both, such as on lines that will be carrying a fair bit of power. 73, Mike KW1ND ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
You are welcome to do both - as long as you don't compromise the contact fit inside the housing. As to whether its worst or even advisable to do both... I've had people tell me that soldering hardens the point where the wire joins the contact and effectively weakens it, because strands can break at that point. I have to say, I would have thought defence contractors would solder as well as crimp, if that was considered worthwhile. FWIW - I havn't soldered any of my crimped APPs. -- Study without desire spoils the memory, and it retains nothing that it takes in. -- Leonardo da Vinci On 17 Mar 2008, at 17:33, Mike B wrote: You either crimp or Solder - not both While it may be easy to prove that doing both is redundant, I see no reason why one *can't* do both, provided you crimp before soldering. I find it rather odd to make such a firm distinction. If I'm planning ahead and remember to bring the crimpers home from work, I'll typically just crimp. Otherwise, I just solder. Sometimes, though, I'll get picky and do both, such as on lines that will be carrying a fair bit of power. 73, Mike KW1ND ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
You either crimp or Solder - not both I crimp and solder. But an explanation is in order: I begin by crimping the PowerPole connector to the stranded wire. When the crimp is complete, I then apply silver bearing solder ONLY to the very tip of the stranded wire where it butts up against the connector. The wire in the area of the crimp has NO solder and this is important to ensure that wire stresses due to cable movement do not break the wire as if it was a solid-conductor. So, it's the best of two worlds as flexibility at the crimp is maintained and I can be sure that long-term resistive loss is minimized by the small application of solder. When using this method, it's critical that the stranded wire does not wick the solder up to the crimp point and that's another reason why I use silver bearing solder as it tendency to flow along the wire is impeded more so than with standard lead/tin solder. Paul, W9AC ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3 power cable
You either crimp or Solder - not both Why not? I've done both on all my crimped connections for years. Crimping breaks through any oxidation in the wire and terminal as well as providing mechanical strength. Soldering adds to both of these as well as reducing the potential for further oxidation (and increased resistance) between the wire and terminal because they are no longer exposed to the environment. Now, if one doesn't have the proper crimping tool and risks distorting the terminal and its fit in the housing or interconnection with its mating terminal, then only soldering may be best. Or, if soldering is not practical for some reason, then crimping is fine. In that case, some dielectric grease on the parts before crimping will help minimize future oxidation and resistance build up. Most of our radio environments are limited enough so lessen the effects of oxidation and mechanical rigidity. But crimping and soldering is so easy to do, why not quickly provide the added margin? 73, Ed - W0YK ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
Ed Muns wrote: You either crimp or Solder - not both Why not? I've done both on all my crimped connections for years. Crimping breaks through any oxidation in the wire and terminal as well as providing mechanical strength. Soldering adds to both of these as well as reducing the potential for further oxidation (and increased resistance) between the wire and terminal because they are no longer exposed to the environment. Now, if one doesn't have the proper crimping tool and risks distorting the terminal and its fit in the housing or interconnection with its mating terminal, then only soldering may be best. Or, if soldering is not practical for some reason, then crimping is fine. In that case, some dielectric grease on the parts before crimping will help minimize future oxidation and resistance build up. Most of our radio environments are limited enough so lessen the effects of oxidation and mechanical rigidity. But crimping and soldering is so easy to do, why not quickly provide the added margin? 73, Ed - W0YK Crimping is only easy to do if you have the tool and are proficient in its use. Some of us need soldering only advice-like where not to get the solder. Power pole connectors are new technology to many of us. Given the problems I've had with past crimping tools, the first couple crimps with a new tool/connector are bad. That shoots down the two connectors supplied. So I guess if I had to buy a tool, I'd also get a bunch of spare connectors too. Not the scenerio I like for a $2K rig. Not an big deal though. 73 de Brian/K3KO. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3 power cable
OK, we've established that the kit rigs require you to assemble the APPs on the wire to make the power cable. Same deal for the factory assembled rigs or do they come with finished power cables? - Keith N1AS - - K2 5411.ssb.100 - - K3 Wave 3 (soon) - ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
The assembled K3's come with an assembled power cable, you just need to finish the battery/power supply side. Jeff On Mon, Mar 17, 2008 at 12:55 PM, Darwin, Keith [EMAIL PROTECTED] wrote: OK, we've established that the kit rigs require you to assemble the APPs on the wire to make the power cable. Same deal for the factory assembled rigs or do they come with finished power cables? - Keith N1AS - - K2 5411.ssb.100 - - K3 Wave 3 (soon) - ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: Re: [Elecraft] K3 power cable
I would far prefer a factory pre-assembled power cable, given the expense of the correct crimp tool and I far prefer crimping to soldering to a cable with no strain relief. ps I've probably crimped and soldered 100s of thousands of wires. But this is not a crimp tool in my armoury. David G3UNA - Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] K3 power cable
Don't over complicate it. I just used a plain old wire crimper and solder. If you want some more strain relief, put some heat shrink tubing over the connector and for about 6 inches up the wire. Use big tubing at the connector and overlap it over smaller tubing up the wire. You might have to overlap a couple of different sizes to get it to be snug but it will be very strong. A drop of hot glue on the end of the power pole would also help. If you could see the Mickey Mouse job Yaesu did on the $4000 Quadra control cables or the pathetic and wimpy connector TenTec used for the Orion, you wouldn't feel so bad about the power poles. k4ia Buck K3 #101 Fredericksburg, VA **It's Tax Time! Get tips, forms, and advice on AOL Money Finance. (http://money.aol.com/tax?NCID=aolprf000301) ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] K3 power cable
Don't worry about doing both... It leaves you that much more sure that you won't lose connection and trust me... The electrons will forgive your soul for doing both! :) -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Mike B Sent: Monday, March 17, 2008 10:34 AM To: Elecraft Reflector Subject: Re: [Elecraft] K3 power cable You either crimp or Solder - not both While it may be easy to prove that doing both is redundant, I see no reason why one *can't* do both, provided you crimp before soldering. I find it rather odd to make such a firm distinction. If I'm planning ahead and remember to bring the crimpers home from work, I'll typically just crimp. Otherwise, I just solder. Sometimes, though, I'll get picky and do both, such as on lines that will be carrying a fair bit of power. 73, Mike KW1ND ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
