Re: [Elecraft] Voltage Drop

Truth be told, I don't think so. I use almost entirely low end consumer stuff, mostly because I blow up at least a meter a year two, when I put the 10A scale across a storage battery, The 750VDC scale across 2KV, or 400V to the low Ohms scale. When it's a free harbor Freight meter, I don't lose

Re: [Elecraft] Voltage Drop

You have trouble with Fluke DMM’s? Sent from my iPhone > On Jun 30, 2020, at 9:06 PM, Wilson Lamb wrote: > > Are we going to talk about RF getting into DMMs? > The DMMs I've used can't be used on tractors or under the hood of cars not > even on the battery, because of ignition noise. >

[Elecraft] Voltage Drop

Are we going to talk about RF getting into DMMs? The DMMs I've used can't be used on tractors or under the hood of cars not even on the battery, because of ignition noise. There's a lot to be said for old school needle meters! WL __

Re: [Elecraft] Voltage drop in DC Power to K3

On 4/26/2020 8:33 PM, Charlie T wrote: From the wire tables, I think you'll find that doubling the number of wires will result in an equivalent of one cable 3 wire sizes larger. Yep. Three wire gauges is double the cross sectional area. 73, Jim K9YC

Re: [Elecraft] Voltage drop in power cable

I wonder what the time constant is for that sense to respond...say to CW or SSB Jack BMW Motorcycles Chuck KE9UW c-haw...@illinois.edu Sent from my iPad > On Apr 27, 2020, at 6:48 AM, Joe wrote: > > For the purest, a possible fix would be to use a power supply that uses > sense leads to

Re: [Elecraft] Voltage drop in DC Power to K3

alf Of Jim Brown Sent: Sunday, April 26, 2020 6:39 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Voltage drop in DC Power to K3 On 4/26/2020 10:18 AM, Pete Lascell wrote: > When making connections unravel a few outside strands and cut off so the remaining strands will fit the terminals

Re: [Elecraft] Voltage drop in power cable

For the purest, a possible fix would be to use a power supply that uses sense leads to regulate the output voltage like my old Lambda power supply does. I don't use the Lambda for the ham shack, but this would solve the problem. The sense leads would be connected as close to the transceiver as

Re: [Elecraft] Voltage drop in DX Power to K3

On 4/26/2020 7:28 PM, N4ZR wrote: did you have to draw a Colpitts oscillator?  IIRC, that was on my General exam in 1955. Yep. It was one of several we had to learn. :) With the power strip, what's wrong with measuring the voltage in and out, knowing the current being drawn, and deriving

Re: [Elecraft] Voltage drop in DX Power to K3

Having helped teach a number of Tech level ham crams, Ohm's law and diodes are both on the test. I'm not sure that all of the nitty gritty of diodes -- voltage drop by type etc. are covered though. I think you can pass not knowing either though. :-( 73 Bill AE6JV On 4/26/20 at 6:24 PM,

Re: [Elecraft] Voltage drop in DC Power to K3

If you really want better connections, try the 75 amp power poles. Of course they are bigger, and not plug compatible with the 15, 30, 45 amp connectors. (And I always thought the only difference between the 15, 30, and 45 amp connectors was the size of wire you could cram into them.) 73

Re: [Elecraft] Voltage drop in DX Power to K3

Gee Jim, I didn't think I was *that* stupid. Yes, I didn't get the decimal places right -that was a simple brain phart.  As for the licensing tests, did you have to draw a Colpitts oscillator?  IIRC, that was on my General exam in 1955. With the power strip, what's wrong with measuring the

Re: [Elecraft] Voltage drop in DC Power to K3

On 4/26/2020 10:18 AM, Pete Lascell wrote: When making connections unravel a few outside strands and cut off so the remaining strands will fit the terminals being used correctly. The smaller (higher resistance) section of cable will be only part of an inch. Heatshrink tubing will cover the

Re: [Elecraft] Voltage drop in DX Power to K3

I wouldn't expect useful accuracy from anything but a lab instrument for such low resistances as a few feet of #12. Far better to look up the resistance of copper wire from a wire table. An unknown "black box" like a power strip is not so easy. :) As for the protection diode, that's pretty

Re: [Elecraft] Voltage drop in power cable

I have always used a power distribution strip in my system. I don't think I've seen my solution to the drop problem mentioned. While there is a practical limit to the wire size usable in APP connectors, with excess positions on the power strip, multiple cables can be used. I ran two heavy (I

Re: [Elecraft] Voltage drop in DC Power to K3

Voltage drop the easy way: 1. Press the DISP button on the K3. 2. Adjust VFO B for voltage. 3. Go into transmit at full power. 4. Write down the voltage you see. 5. Meter the power supply. 6. Go into full power transmit. 7. Write down the Power Supply voltage. Subtract the number you got

Re: [Elecraft] Voltage drop in DC Power to K3

; - Original Message - > From: Leroy Buller > To: N4ZR > Cc: Elecraft List > Sent: 4/26/2020 11:53:28 AM > Subject: Re: [Elecraft] Voltage drop in DX Power to K3 > > > 40 inches of power

Re: [Elecraft] Voltage drop in DC Power to K3

, the resistance can be as little as 35% of the larger #10 cable. Pete W4WWQ - Original Message - From: Leroy Buller To: N4ZR Cc: Elecraft List Sent: 4/26/2020 11:53:28 AM Subject: Re: [Elecraft] Voltage drop in DX Power to K3

Re: [Elecraft] Voltage drop in DX Power to K3

Thanks, Bob - I had forgotten about being able to measure at the acc 12v output.  In any case, though, the front-panel display provides a pretty good number.  It says that the RX-only voltage at the K3 is 13.7 volts.  My worst-case at 100 watts key down is 12.6 - I don't know where the 11

Re: [Elecraft] Voltage drop in DX Power to K3

Pete:  Sorry I read some of your numbers incorrectly.  A cable with 0.3 ohms resistance and 20 amps of current will have a voltage drop of 20 x 0.3 for 6 volts.  This can't be correct. More like 20 x 0.03 for 1.2 volts.   Still too much. Don't try to measure resistance with a DVM, as point

Re: [Elecraft] Voltage drop in DX Power to K3

Aside from  my decimal point problems  The cable measured 0.3 ohms, with my DMM, but in retrospect, its measurement could not have been correct. However, the measurement on the 4005i is about right, because that was done by comparing the voltages at its input and output, and was at 100

Re: [Elecraft] Voltage drop in DX Power to K3

Oh well, I need another cup of coffee.    I'll try to do better proof reading.  Can't blame that one on auto-correct! Cutting to the chase., measure from the power supply POS terminal to the ACC 12V on the K3 radio.    That is the total voltage drop in the POS DC path.  Then do the

Re: [Elecraft] Voltage drop in DX Power to K3

ment on the power supply line will "see" a varying power supply. This solution is used in many different pieces of equipment in broadcasting. 73 George AI4VZ -Original Message- From: David Herring Sent: Sunday, April 26, 2020 11:08 AM To: N4ZR Cc: Elecraft List Subject: Re: [Elecraft

Re: [Elecraft] Voltage drop in DX Power to K3

There is one more item that has been forgotten. The K3 has an SB530 Schottky diode in the power input circuit between the input fuse and the main 12V bus (but not the 100 watt 12V PA bus). This will account for about a half of a volt drop. If you are using the front panel voltage reading, this

Re: [Elecraft] Voltage drop in DX Power to K3

I got a good chuckle out of that one Bob, happens to me often take 2 > The calculation is simple:    E = I x R  current multiplied by resistance equals the voltage. The calculation is simple:    E = I x R  current multiplied by amps equal voltage. 73 Bob, K4TAX

Re: [Elecraft] Voltage drop in DX Power to K3

Approximately .3 volts with a cable about a foot long. 73, Pete N4ZR Check out the Reverse Beacon Network at , now spotting RTTY activity worldwide. For spots, please use your favorite "retail" DX cluster. On 4/26/2020 11:08 AM, David Herring wrote: I’m late in coming

Re: [Elecraft] Voltage drop in DX Power to K3

The power cable at 0.03 ohms on each side,  a total of 0.06 ohms resistance.  The 4005i, per his measurements, has 0.08 ohms resistance.   The power distribution strip contributes more than 50% of the voltage drop.   Actually more than the power cables. The power cable contributes  1.2 volts

Re: [Elecraft] Voltage drop in DX Power to K3

40 inches of power cable. In my experiences, that could be an issue depending on the gauge of the wire. I used a long cable 12 gauge and had issues. Went to 24 inches number 10 gauge and voltage drop significantly improved. The resustace does not have to be large to cause a voltage drop Lee

Re: [Elecraft] Voltage drop in DX Power to K3

I’m late in coming to this thread, so sorry if I missed the answer to this question, but what is the voltage drop between the power supply and the 4005i? 73, David N5DCH > On Apr 26, 2020, at 8:46 AM, N4ZR wrote: > > I've had an e-mail exchange with West Mountain Radio. Measured the voltage

[Elecraft] Voltage drop in DX Power to K3

I've had an e-mail exchange with West Mountain Radio.  Measured the voltage drop inside the 4005i at only .08 volts at 100 watts key down.  My power cable from the 4500i to the K3 measures 0.3 ohms on each conductor, which at 20 amps should only yield a 1.2 volt drop, right?  I don't know

[Elecraft] voltage drop

anybody know what size power supply wire is supplied with the K3? __ 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