Re: [Elecraft] CW problem

[rv6amark via Elecraft]

John,Re:  "Anytime I change the mode from LSB or USB on any band to CW it 
starts to send a “dit” without stopping..."Take a look at the plug and jack.  
Be sure there is no damage to the jack, and that none of the plug was left 
behind in the jack.  That happened to me once on a keyboard.  A part of the 
plug's barrel broke off and just happened to short the tip to the shield.  It 
was difficult to see, too. It's a long shot, and may not be what happened in 
your case, but the symptoms are correct.Mark,KE6BB
null
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Re: [Elecraft] K1 Intermittent Frequency Instability

[Bert]

Hi Chris,

Instead of spending time troubleshooting I would start with re-soldering
the Front Panel Board and connections. There are not that many
components so it shouldn't take that long. I had an intermittent
problem on my K1 and re-soldered the whole RF Board. Not very
sophisticated but it works.

Good luck!

Bert VE3NR




On 7/5/2019 7:01 PM, Christopher Bowne wrote:

My 40 and 20 meter K1 has developed intermittent frequency instability and 
sometimes complete loss of ability to tune (frequency display jumps and stays 
on 68.0 nominal on 40 and 63.0 nominal on 20). Lightly “mechanically agitating” 
the circuit board just behind the front panel will bring it back into stable 
operation, but any sort of movement (I run it QRP mobile in a Tacoma 4x4) will 
throw it out of whack again.  Three modes - normal stable, squiggly unstable, 
and locked at nominal 68 or 63 above 7.0 or 14.0 as noted above.  Seems like a 
bad solder joint or solder whisker somewhere.  Any suggestions on where to 
look?  K1 S/N 0291.

Chris, AJ1G Stonington CT
  from my iPhone
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[Elecraft] K1 Intermittent Frequency Instability

[Christopher Bowne]

My 40 and 20 meter K1 has developed intermittent frequency instability and 
sometimes complete loss of ability to tune (frequency display jumps and stays 
on 68.0 nominal on 40 and 63.0 nominal on 20). Lightly “mechanically agitating” 
the circuit board just behind the front panel will bring it back into stable 
operation, but any sort of movement (I run it QRP mobile in a Tacoma 4x4) will 
throw it out of whack again.  Three modes - normal stable, squiggly unstable, 
and locked at nominal 68 or 63 above 7.0 or 14.0 as noted above.  Seems like a 
bad solder joint or solder whisker somewhere.  Any suggestions on where to 
look?  K1 S/N 0291.

Chris, AJ1G Stonington CT
 from my iPhone
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Re: [Elecraft] Follow up on "Digital modes on 144MHz only"

[Oliver Dröse]

Hi Kjeld,

I'm using the internal K144XV in one my K3s. It's very sensitive and 
stable (using the REFLOCK board, too), so no problem on that. BUT: the 
cooling design is just terrible! :-( It's all passive relying on the 
side plate of the transceiver to dissipate the heat. While this works 
ok-ish on SSB it's a nightmare on CW and especially digimodes! Heat does 
not get dissipated fast enough so the whole transverter heats up quite 
fast which results in a serious power drop, in my case from 10 watts 
down to about 5-6 watts! :-( That means instead of 1 kW output it's just 
5-600 W after about 10 minutes of operation with my PA behind. :-(


I had a second K144XV and behaviour was the same. Same is true for a 
third one at a friend of mine so I assume this is a general design flaw. :-(


I can only second Conrad's, PA5Y, suggestion concerning the HA1YA 
transverter. Very good performance and reasonably priced compared to the 
Kuhne stuff (which is probably even a tad better). Using the PRO models 
myself on 4 & 2 m.


@Wayne:
If you're reading this please make sure the planned 144/430 MHz module 
in the K4 will work much better! Serious DX on VHF is almost all digital 
nowadays and the internal transverter needs to handle that ...


73, Olli - DH8BQA

Contest, DX & radio projects: https://www.dh8bqa.de/


Am 05.07.2019 um 20:34 schrieb Kjeld Holm:

Thanks to all who replied to my mail (see below) but allow me to ask:

Anyone using Elecraft XV144 or K144XV or HG 144-K for digital modes?

Any comments on these being better or worse than other brands?

Vy 73 de OZ1CCM, Kjeld

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Kjeld Holm
Sent: 4. juli 2019 20:31
To: Elecraft Reflector
Subject: [Elecraft] Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you 
look at performance only (no price, no ergonomics, no use outside digital modes 
on 144MHz) what would you prefer

1)   K3/K3S with internal transverter
2)   IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Frank Krozel]

I have a plain K3 that I bypass the built-in tuner on 80 all the time.
On 20 and 40 it is in-line all the time.
de Frank KG9H


> On Jul 5, 2019, at 4:42 PM, Jack Brindle via Elecraft 
>  wrote:
> 
> Good observation, George. The KAT3A indeed does have a bypass relay, while 
> the KAT3 (in the original K3) does not. As I recall, the KAT3 switches the 
> inductors and capacitors out in bypass mode, but does not necessarily provide 
> the best 50 match. This is due to variances in the components and placement 
> from unit to unit. Tuning into a good 50 ohm dummy load can provide a better 
> 50 ohm match, but it has the slight down side of adding a slight amount of 
> loss to the path. In the end they do pretty much the same thing, but if 
> someone wanted to be a real perfectionist (and I’ll admit to that with many 
> things), then tuning into a dummy load will provide an oh-so slightly better 
> match.
> 
> The important point here is that it really needs to tune into a known-good 50 
> ohm resistive load to get what you want. Tuning into the BPF might get you 
> there depending on the output of the BPF.
> 
> As I stated earlier, I set my K3s to bypass mode for driving either my BPFs 
> or my KPA500s.
> 
> 73!
> Jack, W6FB
> 
>> On Jul 5, 2019, at 12:56 PM, Gmail - George  wrote:
>> 
>> 
>> 
>> -Original Message- 
>> From: Jack Brindle via Elecraft 
>> 
>> ...
>> 
>> Now having said this, the ATU can also be bypassed in the K3, and that 
>> circuit may provide a proper 50 ohm source/load for the BPF. I would 
>> probably take this approach myself (and in fact do so in my station). The 
>> reason I take this approach is to avoid the small loss that the internal ATU 
>> presents. In contesting, every db matters.
>> 
>> Note that we are talking nits at this point. Unless the ATU was tuned for a 
>> load quite a bit off 50 ohms resistive, (quite possible), then retuning 
>> won’t make much difference. Perhaps the op had this situation, and thought 
>> it better to return the ATU than to bypass it, or he didn’t even think to 
>> bypass it. The point is, both methods will work, and I doubt he did anything 
>> wrong it performing the tune.
>> 
>> 
>> Jack,
>> If I'm not mistaken - the KAT3 is not able to be physically  bypassed in a 
>> K3 - don't know in a K3S; but I thought the KAT3A  did a physical bypass. 
>> My understanding is that when you bypass the ATU (KAT3), it is merely being 
>> set to a value that cancels the internal L & C of the board.
>> I would think a tune would not actually actually change much of anything; 
>> but leave it to someone to actually test the true output impedance in both.
>> 
>> 73
>> George AI4VZ
>> 
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Jack Brindle via Elecraft]

Good observation, George. The KAT3A indeed does have a bypass relay, while the 
KAT3 (in the original K3) does not. As I recall, the KAT3 switches the 
inductors and capacitors out in bypass mode, but does not necessarily provide 
the best 50 match. This is due to variances in the components and placement 
from unit to unit. Tuning into a good 50 ohm dummy load can provide a better 50 
ohm match, but it has the slight down side of adding a slight amount of loss to 
the path. In the end they do pretty much the same thing, but if someone wanted 
to be a real perfectionist (and I’ll admit to that with many things), then 
tuning into a dummy load will provide an oh-so slightly better match.

The important point here is that it really needs to tune into a known-good 50 
ohm resistive load to get what you want. Tuning into the BPF might get you 
there depending on the output of the BPF.

As I stated earlier, I set my K3s to bypass mode for driving either my BPFs or 
my KPA500s.

73!
Jack, W6FB

> On Jul 5, 2019, at 12:56 PM, Gmail - George  wrote:
> 
> 
> 
> -Original Message- 
> From: Jack Brindle via Elecraft 
> 
> ...
> 
> Now having said this, the ATU can also be bypassed in the K3, and that 
> circuit may provide a proper 50 ohm source/load for the BPF. I would probably 
> take this approach myself (and in fact do so in my station). The reason I 
> take this approach is to avoid the small loss that the internal ATU presents. 
> In contesting, every db matters.
> 
> Note that we are talking nits at this point. Unless the ATU was tuned for a 
> load quite a bit off 50 ohms resistive, (quite possible), then retuning won’t 
> make much difference. Perhaps the op had this situation, and thought it 
> better to return the ATU than to bypass it, or he didn’t even think to bypass 
> it. The point is, both methods will work, and I doubt he did anything wrong 
> it performing the tune.
> 
> 
> Jack,
> If I'm not mistaken - the KAT3 is not able to be physically  bypassed in a K3 
> - don't know in a K3S; but I thought the KAT3A  did a physical bypass. 
> My understanding is that when you bypass the ATU (KAT3), it is merely being 
> set to a value that cancels the internal L & C of the board.
> I would think a tune would not actually actually change much of anything; but 
> leave it to someone to actually test the true output impedance in both.
> 
> 73
> George AI4VZ
> 
> ---
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Re: [Elecraft] Fwd: K4/K4D antenna ports.

[Nr4c]

Thank you, Wayne. 

Sent from my iPhone
...nr4c. bill


> On Jul 5, 2019, at 12:59 PM, Wayne Burdick  wrote:
> 
> Nr4c  wrote:
> 
> 
>>> How many ports does a K4D have without the ATU. 
> 
> 1 main antenna jack and 2 receive antenna inputs.
> 
> 
>>> 
>>> I know the K4 only has one I think the ATU ads 2 more for total of three. 
> 
> Yes. Also, any one of the ATU antenna jacks can be designated as a third 
> receive antenna input (for either receiver).
> 
> 
>>> But K4D must have two ports for separate antennas for Diversity, right?
> 
> Yes, RX ANT1 and RX ANT2. The latter is also labeled XVTR IN, and can be used 
> with transverters.
> 
> 73,
> Wayne
> N6KR
> 

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Re: [Elecraft] KX3 Headphone set up problem

[Mark Goldberg]

The exact cable Wunder suggested is still available at Amazon for $4.95.
They can probably thank him for some sales! I bought one.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 1:11 PM Don Wilhelm  wrote:

> Note carefully that Wunder specified a "SPLITTER" and that is different
> than an 'adapter'.
>
> The more common mono to stereo adapter will NOT cure the condition.
>
> 73,
> Don W3FPR
>
> On 7/5/2019 3:28 PM, Walter Underwood wrote:
> > The mic plug is shorting the “mic button” (PTT) contact. Set MIC BTN to
> OFF in the menus or use an off the shelf stereo to mono splitter.
> >
> > I described the latter in this blog post. The splitter also gives you
> cleaner mic bias and a PTT jack.
> >
> >
> https://observer.wunderwood.org/2015/08/16/yamaha-cm500-headset-with-ptt-on-elecraft-kx3/
> >
> > wunder
> > K6WRU
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Mark Goldberg]

On Fri, Jul 5, 2019 at 12:54 PM Jack Brindle via Elecraft <
elecraft@mailman.qth.net> wrote:

> As commonly used, bandpass filters have one main use - to protect
> receivers. That may be the local receiver, protecting it from sting out of
> band signals, or a neighbor receiver, gain protecting it from strong out of
> band signals.
>

You are only thinking of good Elecraft radios. There are plenty of crap
radios that transmit harmonics or even wideband noise.


> This quite well describes SO2R stations, where we are very concerned about
> receiver damage. The BPF is commonly placed between the transceiver and
> antenna, which for a multiple of reasons needs to be 50 ohms impedance.
> One of the major jobs given to the BPF is to suppress harmonic content of
> the transmitted signal, for which the antenna load will most certainly NOT
> present a 50 ohm load to the BPF. There are many references for this, I
> would refer to W2VJN’s publication “Managing Interstaion Interference” and
> the excellent articles by K9YC (who will most likely join into the
> discussion shortly). Jim has done a lot of testing with BPFs, and has some
> very interesting articles comparing and discussing their use, as well as
> other articles about how to avoid damaging receivers in SO2R stations with
> their use, as well as the use of stubs for harmonic suppression.
>
> The point is, BPFs are designed for both scenarios, to pass signals
> in-band, where the load impedance is 50 ohms, and reject out of band
> signals, where the impedance is almost never50 ohms. Note that most BPFs do
> not do much for in-band signal rejection (by design). Using them to protect
> a receiver in the same band is a recipe for disaster.
>
>
In general a BPF will present a low impedance shunt load and a high
impedance series load. Even into an unmatched load, it is likely that the
BPF will still have a much lower shunt impedance and a much higher series
impedance than what it is working into. In the example I showed, the change
out of the passband was much less than the change in the passband. Out of
the passband, it still works pretty well to reject signals. The unmatched
load affects the in band performance a lot.

I found Elsie to be really useful to get an understanding of what filters
do under various conditions.

73,

Mark
W7MLG
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Re: [Elecraft] KX3 Headphone set up problem

[Don Wilhelm]

Note carefully that Wunder specified a "SPLITTER" and that is different 
than an 'adapter'.


The more common mono to stereo adapter will NOT cure the condition.

73,
Don W3FPR

On 7/5/2019 3:28 PM, Walter Underwood wrote:

The mic plug is shorting the “mic button” (PTT) contact. Set MIC BTN to OFF in 
the menus or use an off the shelf stereo to mono splitter.

I described the latter in this blog post. The splitter also gives you cleaner 
mic bias and a PTT jack.

https://observer.wunderwood.org/2015/08/16/yamaha-cm500-headset-with-ptt-on-elecraft-kx3/

wunder
K6WRU

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Re: [Elecraft] OT a bit: K3 Ant Tuner

[David Woolley]

I think we have the maximum power transfer theorem fallacy again here. 
The maximum power transfer theorem does not give the right result when 
you want to maximise efficiency, which is what you generally want to do 
in a transmitter, as it always results in worse than 50% efficiency.


One would expect the output impedance of transmitter to not only differ 
from 50 ohms but to radically differ from it.  If I remember correctly 
for a simple transconductance device, the resistive component will be 
many times 50 ohms.  If heavy negative feedback is used, I think it may 
actually be much lower than the "matched" value.  See 
 for typical real 
reverse termination impedances.


Unless you put a (ferrite) isolator between transmitter and filter your 
filter design needs to assume far from 50 ohm reverse termination.


Putting a matching network in will simply destroy the PA efficiency, or 
even destroy the PA, through overheating.  If one really wanted to do 
it, you would have to adjust the SWR based on a received signal.


That matching network, will, itself, have a frequency response, as will 
the one leading to antenna.


Another reason for not operating anywhere near 50 ohm reverse terminated 
is that the dynamic resistance of output devices is far from linear, and 
a close match could produce a lot of distortion.


--
David Woolley
Owner K2 06123

On 05/07/2019 18:55, Jack Brindle wrote:

Lets step back a bit and look at the system here. The K3, with ATU, drives into 
the BPF, when then drives into the external ATU and finally the antenna.
The external ATU takes care of the antenna matching, and should present a 50 
ohm load to the BPF. The BPF, because of its design, should present a 50 ohm 
load to the ATU as well, so everything is matched there.
Before anyone jumps on this, remember the signals go both ways, outbound for 
transmit, inbound for receive. Also, we have a fundamental principal thrown at 
every EE student, that for best transmission of signal, the source and load 
impedances should match.


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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Gmail - George]

-Original Message- 
From: Jack Brindle via Elecraft 

...

Now having said this, the ATU can also be bypassed in the K3, and that circuit 
may provide a proper 50 ohm source/load for the BPF. I would probably take this 
approach myself (and in fact do so in my station). The reason I take this 
approach is to avoid the small loss that the internal ATU presents. In 
contesting, every db matters.

Note that we are talking nits at this point. Unless the ATU was tuned for a 
load quite a bit off 50 ohms resistive, (quite possible), then retuning won’t 
make much difference. Perhaps the op had this situation, and thought it better 
to return the ATU than to bypass it, or he didn’t even think to bypass it. The 
point is, both methods will work, and I doubt he did anything wrong it 
performing the tune.


Jack,
If I'm not mistaken - the KAT3 is not able to be physically  bypassed in a K3 - 
don't know in a K3S; but I thought the KAT3A  did a physical bypass. 
My understanding is that when you bypass the ATU (KAT3), it is merely being set 
to a value that cancels the internal L & C of the board.
I would think a tune would not actually actually change much of anything; but 
leave it to someone to actually test the true output impedance in both.

73
George AI4VZ

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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Jack Brindle via Elecraft]

As commonly used, bandpass filters have one main use - to protect receivers. 
That may be the local receiver, protecting it from sting out of band signals, 
or a neighbor receiver, gain protecting it from strong out of band signals.
This quite well describes SO2R stations, where we are very concerned about 
receiver damage. The BPF is commonly placed between the transceiver and 
antenna, which for a multiple of reasons needs to be 50 ohms impedance.
One of the major jobs given to the BPF is to suppress harmonic content of the 
transmitted signal, for which the antenna load will most certainly NOT present 
a 50 ohm load to the BPF. There are many references for this, I would refer to 
W2VJN’s publication “Managing Interstaion Interference” and the excellent 
articles by K9YC (who will most likely join into the discussion shortly). Jim 
has done a lot of testing with BPFs, and has some very interesting articles 
comparing and discussing their use, as well as other articles about how to 
avoid damaging receivers in SO2R stations with their use, as well as the use of 
stubs for harmonic suppression.

The point is, BPFs are designed for both scenarios, to pass signals in-band, 
where the load impedance is 50 ohms, and reject out of band signals, where the 
impedance is almost never50 ohms. Note that most BPFs do not do much for 
in-band signal rejection (by design). Using them to protect a receiver in the 
same band is a recipe for disaster.

There is another point being missed. The K3 design, like most transceivers, 
contains a Low Pass filter (LPF) after the PA (used for both the low power 
output and the KPA3 if installed), followed by a directional coupler. The 
directional coupler needs to see 50 ohms at both the input and output for it to 
measure signals accurately. It can pretty well be assumed that when the 
internal ATU is in bypass, the K3 is close to 50 ohms at the antenna port. 
Thus, in bypass, the BPF should see the load it needs at its output. 

Again, the purpose of the BPF is to protect receivers, so the load we generally 
discuss is the K3 receiver, which will be 50 ohms due to the directional 
coupler input, But we also need for it to see an in-band 50 ohm load at its 
other end so that it can properly do its job. Note that BPFs are bidirectional 
- it really doesn’t matter how you connect them they do the same job both ways. 
They will generally see higher signal levels when in the active TX path (and 
thus dissipate more heat), but they are active in both directions, and for 
passing signals with very little loss, need to see a proper load.

73!
Jack, W6FB

> On Jul 5, 2019, at 12:27 PM, Joe Subich, W4TV  wrote:
> 
> On 2019-07-05 1:55 PM, Jack Brindle via Elecraft wrote:
> 
>> The external ATU takes care of the antenna matching, and should 
> > present a 50 ohm load to the BPF.
> 
> This only hold true for the *single frequency* on which the external
> antenna tuner is "tuned".  Typically (depending on the tuner Q and
> losses), the SWR seen by the BPF will be *HIGHER* away from the one
> "matched" frequency (e.g., the other end of the band) than it would
> be without the external tuner in place.
> 
> As such, the tuner in/tuner out will increase losses and heating in
> the BPF.  If the BPF is a marginal design, the added loss/heat could
> be fatal to the BPF.
> 
> The proper way to handle a rig with built-in tuner is to bypass the
> internal tuner (or tune it into a 50 Ohm load in the middle of the
> band) and do *all tuning with the external tuner* which assures the
> BPF always sees a 50 OHM load.
> 
> 73,
> 
>   ... Joe, W4TV
> 
> 
> On 2019-07-05 1:55 PM, Jack Brindle via Elecraft wrote:
>> Lets step back a bit and look at the system here. The K3, with ATU, drives 
>> into the BPF, when then drives into the external ATU and finally the antenna.
>> The external ATU takes care of the antenna matching, and should present a 50 
>> ohm load to the BPF. The BPF, because of its design, should present a 50 ohm 
>> load to the ATU as well, so everything is matched there.
>> Before anyone jumps on this, remember the signals go both ways, outbound for 
>> transmit, inbound for receive. Also, we have a fundamental principal thrown 
>> at every EE student, that for best transmission of signal, the source and 
>> load impedances should match.
>> OK, so let’s look at the K3 side. The K3 antenna port connects directly to 
>> the BPF’s radio port. Again, we are presuming the BPF is designed for 50 
>> ohms resistive source/load. The K3 is designed to transmit into a 50 ohm 
>> load, but it may not itself be a 50 ohm source. And, the receiver input may 
>> not be 50 ohms as well. Adding a tuned ATU does bring this to 50 ohms, 
>> providing a proper match into the BPF, so that optimum signal flows both 
>> ways. So it could actually be beneficial for the ATU to be in-line and 
>> properly tuned. The best way to perform the tune would be to tune the ATU 
>> into a 50 ohm dummy load, but tuning into the 

Re: [Elecraft] OT a bit: K3 Ant Tuner

[Jim Brown]

Actually, I suspect that they're designed for 50 ohms at least in part, 
because that's how they will be measured!  We try hard to present a 
matched load in the passband, but, as others observed, output stages are 
usually lower than 50 ohms and few antennas, even when matched by a 
tuner, look anything like 50 ohms away from resonance. So all we can 
really hope to gain by matching is to minimize loss in the passband.  
AND -- any performance specs and/or measurements at 50 ohms in and out 
are a fiction away from resonance, and with other than a 50 ohm source.


73, Jim K9YC



On 7/5/2019 11:37 AM, K9MA wrote:
Bandpass filters are generally designed for 50 Ohm source and load 
resistances, mainly because the actual source and load impedances are 
usually unknown. These filters will only perform as advertised with a 
50 Ohm source and load. With real world impedances, you just have to 
hope for the best.



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Re: [Elecraft] Digital modes on 144MHz only

[Conrad PA5Y]

Wes is quite right. 

There is a free program called AppCAD that allows system noise figure analysis 
for up to 7 cascaded stages. It is enlightening and you will understand the 
significance of each stage in no time just by plugging a few numbers in. Have a 
try its educational 

73

Conrad PA5Y

-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Wes
Sent: 05 July 2019 15:08
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] Digital modes on 144MHz only

That isn't quite right either.  The preamp gain must be much higher than the 
following losses to minimize second stage degradation. (Line loss degrades the 
NF of the second stage)

Wes  N7WS

On 7/5/2019 5:35 AM, Martin wrote:
>
> That's not quite right. The overall system noise is determined by the 
> preamp noise figure when mounted as close  to the antenna as possible. 
> Cable losses
> (=noise) after the preamp can be neglected, as long as the gain of the 
> preamp is higher than the losses in subsequent components. So the 
> cable AFTER the preamp can be pretty lossy. OTOH, too much gain from 
> the preamp easily overdrives your transceiver's RX. A good balance 
> between gain vs. cable losses is mandatory. The noise figure of the pramp is 
> crucial.
> If you are satisfied with your transverter's noise figure , mount it 
> close to the antenna via a short run low loss cable, if you can. This 
> saves the expenses for a preamp.
>
> This applies to the RX path. I'm not talking cable quality or output 
> power for TX.
>
>
> > Message: 15
> > Date: Thu, 4 Jul 2019 17:11:58 -0500
> > From: Bob McGraw K4TAX 
> > To: elecraft@mailman.qth.net
> > Subject: Re: [Elecraft] Digital modes on 144MHz only
> >
> > . Start with a mast mounted low noise preamp, then low loss 
> > feedline such as 7/8" hard-line, and such. Remember, loss in the 
> > feedline adds to receiver noise.
> > ..
> >
>
>

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[Elecraft] K3S TX IMD on 50 MHz

[Conrad PA5Y]

In the last few weeks I have been setting up my K3S with transverters and using 
the on board 2 tone generator and a 28 MHz transverter drive I have been 
delighted with the TX performance. The 3rd order TX IMD at the level I require 
is -58dBc! It is how radios should be. Tonight I am making these measurements 
on 6m at various power levels and they are awful! Not only that but 
occasionally I see some strange gain jumps, usually when I first start the 2 
tone test. I have read that this hunting is due to the power control loop.

So I hope that adding the PA means that I am doing something wrong with the 2 
tone setup. I have the compression set to zero but I think that this is 
bypassed when internal 2 tone generator is active? I cannot get 3rd orders 
better than -26dBc on 6m at any power level. I read about the ALC 'hunting' but 
when on LSB with 2 tone on I see no ALC indication at all so maybe this is the 
problem? At 10W there is an awful noise pedestal as well. I hope that this is 
not AM noise as seen on the IC-7300. Please tell me that this I an adjustment 
error on my part or I will have to add a PA to the transverter port for 6m.

Help!

73

Conrad PA5Y
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Re: [Elecraft] KX3 Headphone set up problem

[Walter Underwood]

The mic plug is shorting the “mic button” (PTT) contact. Set MIC BTN to OFF in 
the menus or use an off the shelf stereo to mono splitter.

I described the latter in this blog post. The splitter also gives you cleaner 
mic bias and a PTT jack.

https://observer.wunderwood.org/2015/08/16/yamaha-cm500-headset-with-ptt-on-elecraft-kx3/

wunder
K6WRU
Walter Underwood
CM87wj
http://observer.wunderwood.org/ (my blog)

> On Jul 5, 2019, at 12:19 PM, Michael Heit via Elecraft 
>  wrote:
> 
> I bought the Heil headphone set up with my KX3 but have never been able to 
> get the mic to work right. I followed the instructions for installing it and 
> the menu items needed but every time I plug in the mic plug the radio 
> immediately goes into transmit mode.
> The reason I wanted the headset was hands free operation, the earphones are 
> great but I cannot use the mic installed? Has anyone else had this problem? 
> Did you cure it? Hos so??
> Thank you,73Mike AD7VV
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Joe Subich, W4TV]

On 2019-07-05 1:55 PM, Jack Brindle via Elecraft wrote:

The external ATU takes care of the antenna matching, and should 

> present a 50 ohm load to the BPF.

This only hold true for the *single frequency* on which the external
antenna tuner is "tuned".  Typically (depending on the tuner Q and
losses), the SWR seen by the BPF will be *HIGHER* away from the one
"matched" frequency (e.g., the other end of the band) than it would
be without the external tuner in place.

As such, the tuner in/tuner out will increase losses and heating in
the BPF.  If the BPF is a marginal design, the added loss/heat could
be fatal to the BPF.

The proper way to handle a rig with built-in tuner is to bypass the
internal tuner (or tune it into a 50 Ohm load in the middle of the
band) and do *all tuning with the external tuner* which assures the
BPF always sees a 50 OHM load.

73,

   ... Joe, W4TV


On 2019-07-05 1:55 PM, Jack Brindle via Elecraft wrote:

Lets step back a bit and look at the system here. The K3, with ATU, drives into 
the BPF, when then drives into the external ATU and finally the antenna.
The external ATU takes care of the antenna matching, and should present a 50 
ohm load to the BPF. The BPF, because of its design, should present a 50 ohm 
load to the ATU as well, so everything is matched there.
Before anyone jumps on this, remember the signals go both ways, outbound for 
transmit, inbound for receive. Also, we have a fundamental principal thrown at 
every EE student, that for best transmission of signal, the source and load 
impedances should match.

OK, so let’s look at the K3 side. The K3 antenna port connects directly to the 
BPF’s radio port. Again, we are presuming the BPF is designed for 50 ohms 
resistive source/load. The K3 is designed to transmit into a 50 ohm load, but 
it may not itself be a 50 ohm source. And, the receiver input may not be 50 
ohms as well. Adding a tuned ATU does bring this to 50 ohms, providing a proper 
match into the BPF, so that optimum signal flows both ways. So it could 
actually be beneficial for the ATU to be in-line and properly tuned. The best 
way to perform the tune would be to tune the ATU into a 50 ohm dummy load, but 
tuning into the BPF at low power should work also. The exception to this would 
be if the BPF changes impedance when power is applied, but then if this happens 
the best place for that BPF is the trash can.

Now having said this, the ATU can also be bypassed in the K3, and that circuit 
may provide a proper 50 ohm source/load for the BPF. I would probably take this 
approach myself (and in fact do so in my station). The reason I take this 
approach is to avoid the small loss that the internal ATU presents. In 
contesting, every db matters.

Note that we are talking nits at this point. Unless the ATU was tuned for a 
load quite a bit off 50 ohms resistive, (quite possible), then retuning won’t 
make much difference. Perhaps the op had this situation, and thought it better 
to return the ATU than to bypass it, or he didn’t even think to bypass it. The 
point is, both methods will work, and I doubt he did anything wrong it 
performing the tune.

73!
Jack, W6FB



On Jul 5, 2019, at 10:18 AM, Mark Goldberg  wrote:

I could not let this go. I've done a lot of work with bandpass filters. The
mismatch will degrade the filter.

For an example, I used Elsie, which is a filter calculator. Using the
example 20 Meter bandpass filter, the passband loss is about .25 dB with
matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
losses increase to about 0.4 - .44 dB and vary more over the band.

Here are the schematics and plots, anyone is welcome to check my
calculations, as I do make mistakes!

https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing

The loss in the filter will almost double. For 100W in, the loss goes from
about 6W to about 10W. So, it is not a good idea. A worse match will result
in even more losses, perhaps overheating and destroying the filter.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm  wrote:


Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more
loss due to inductor winding resistance, but other than that, it should
do harm.

Several bandpass filters indicate that they should be between the rig
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to
the rig power, then I would observe that caution. Refer to the bandpass
filter specs.

73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:

To minimize emails direct replies would be nice.  I searched the web and
could not find an answer.   I know there are a ton of smart folks on
this list so I thought I would ask.

On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the 

Re: [Elecraft] (no subject)

[John Stengrevics]

A bit off topic, but I thought I’d ask anyway.  Would using a HA1YA 6 meter 
transverter with the K3S improve performance on noise level reduction and 
sensitivity over the stock K3S?

73,

John
WA1EAZ



> On Jul 5, 2019, at 3:17 PM, Conrad PA5Y  wrote:
> 
> Hello Ed, the HA1YA and DB6NT transverters are also considerably better than 
> the DEMI designs which are 3 generations behind. I have been in serious 
> pursuit of low PN and low IMD on 144 and 432 and I found that either of the 
> aforementioned transverters with a K3S were many times better than anything 
> else. I looked at almost everything out there, it took 2 years but there 
> really was no other choice. There used to be 3 choices but sadly the Anglian 
> (144) and Iceni (432) kits from G4DDK are no longer an option, on 70cms I 
> have an Iceni. With the K3S , Iceni and a TV TX I am achieving TX 3rd orders 
> of -53dBc, I am so pleased with this. The composite noise @ 20kHz is 33dBc/Hz 
> better than any other radio that I have measured. On 2m 25dB better for 
> composite noise I am still working on 2m intemods, so far the whole chain is 
> -40dbc 3rd orders but I would like to improve this by at least 6dB, the 
> problem is an LDMOS driver and nothing to do with the K3S or HA1YA 
> transverter.
> 
> I have a bit more to say about the K3S and TX IMD on 6m in another post.
> 
> Regards
> 
> Conrad PA5Y
> 
> -Original Message-
> From: elecraft-boun...@mailman.qth.net  On 
> Behalf Of Edward R Cole
> Sent: 05 July 2019 18:02
> To: Elecraft Reflector 
> Subject: [Elecraft] (no subject)
> 
> Kjeld,
> 
> I agree with Conrad PA5Y,  both Kuhne Engineering or  HA1YA make very good 
> transverters and are available in EU.
> 
> I would add the DEMI L-series transverter which now is made by a company 
> called Q5 (located in US) for any NA hams reading the mail on this topic.
> I use DEMI transverters on digital-eme on 144, 1296, and higher (have had 
> 144,222, 432, 1296, 3456, and 10-GHz models).
> 
> I also use preamps located at antennas on 6m, 2m, 432, 1296+  Even though 
> local electronic noise can be high at times, when its not they make a huge 
> difference.  Only for 6m (50-MHz) would I agree that it might not give much 
> help (but if you have a K3, it needs either a PR6 or other preamp to bring up 
> 6m &10m sensitivity; not an issue with K3s or K4).  MY KX3 with internal 
> preamp ON = my K3 + PR6 in sensitivity on 6m)
> 
> The early reports on the IC-9700 were not favorable for freq stability 
> (though I read they had addressed this, lately).  Still investment in K3s + 
> good transverter will beat the IC-9700 without a doubt.
> 
> 73, Ed - KL7UW
> 
> From: Kjeld Holm 
> To: Elecraft Reflector 
> Subject: [Elecraft] Digital modes on 144MHz only
> Message-ID:
> 
> 
> 
> Content-Type: text/plain; charset="us-ascii"
> 
> Digital modes on 144MHz only
> 
> I plan for a second station to use for digital modes on 144MHz only. 
> If you look at performance only (no price, no ergonomics, no use outside 
> digital modes on 144MHz) what would you prefer
> 
> 1)   K3/K3S with internal transverter
> 2)   IC-9700
> 
> In both cases I plan to use a 1kW amplifier.
> 
> Vy 73 de OZ1CCM, Kjeld
> 
> 
> 73, Ed - KL7UW
>   http://www.kl7uw.com
> Dubus-NA Business mail:
>   dubus...@gmail.com 
> 
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[Elecraft] KX3 Headphone set up problem

[Michael Heit via Elecraft]

I bought the Heil headphone set up with my KX3 but have never been able to get 
the mic to work right. I followed the instructions for installing it and the 
menu items needed but every time I plug in the mic plug the radio immediately 
goes into transmit mode.
The reason I wanted the headset was hands free operation, the earphones are 
great but I cannot use the mic installed? Has anyone else had this problem? Did 
you cure it? Hos so??
Thank you,73Mike AD7VV
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Re: [Elecraft] (no subject)

[Conrad PA5Y]

Hello Ed, the HA1YA and DB6NT transverters are also considerably better than 
the DEMI designs which are 3 generations behind. I have been in serious pursuit 
of low PN and low IMD on 144 and 432 and I found that either of the 
aforementioned transverters with a K3S were many times better than anything 
else. I looked at almost everything out there, it took 2 years but there really 
was no other choice. There used to be 3 choices but sadly the Anglian (144) and 
Iceni (432) kits from G4DDK are no longer an option, on 70cms I have an Iceni. 
With the K3S , Iceni and a TV TX I am achieving TX 3rd orders of -53dBc, I am 
so pleased with this. The composite noise @ 20kHz is 33dBc/Hz better than any 
other radio that I have measured. On 2m 25dB better for composite noise I am 
still working on 2m intemods, so far the whole chain is -40dbc 3rd orders but I 
would like to improve this by at least 6dB, the problem is an LDMOS driver and 
nothing to do with the K3S or HA1YA transverter.

I have a bit more to say about the K3S and TX IMD on 6m in another post.

Regards

Conrad PA5Y

-Original Message-
From: elecraft-boun...@mailman.qth.net  On 
Behalf Of Edward R Cole
Sent: 05 July 2019 18:02
To: Elecraft Reflector 
Subject: [Elecraft] (no subject)

Kjeld,

I agree with Conrad PA5Y,  both Kuhne Engineering or  HA1YA make very good 
transverters and are available in EU.

I would add the DEMI L-series transverter which now is made by a company called 
Q5 (located in US) for any NA hams reading the mail on this topic.
I use DEMI transverters on digital-eme on 144, 1296, and higher (have had 
144,222, 432, 1296, 3456, and 10-GHz models).

I also use preamps located at antennas on 6m, 2m, 432, 1296+  Even though local 
electronic noise can be high at times, when its not they make a huge 
difference.  Only for 6m (50-MHz) would I agree that it might not give much 
help (but if you have a K3, it needs either a PR6 or other preamp to bring up 
6m &10m sensitivity; not an issue with K3s or K4).  MY KX3 with internal preamp 
ON = my K3 + PR6 in sensitivity on 6m)

The early reports on the IC-9700 were not favorable for freq stability (though 
I read they had addressed this, lately).  Still investment in K3s + good 
transverter will beat the IC-9700 without a doubt.

73, Ed - KL7UW

From: Kjeld Holm 
To: Elecraft Reflector 
Subject: [Elecraft] Digital modes on 144MHz only
Message-ID:
 


Content-Type: text/plain; charset="us-ascii"

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. 
If you look at performance only (no price, no ergonomics, no use outside 
digital modes on 144MHz) what would you prefer

1)   K3/K3S with internal transverter
2)   IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld


73, Ed - KL7UW
   http://www.kl7uw.com
Dubus-NA Business mail:
   dubus...@gmail.com 

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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Bob McGraw K4TAX]

A bandpass filter is designed for optimum rejection and pass frequencies 
only when operated at 50 ohms.  Thus both ends of the filter need to see 
50 ohms.  If the antenna has a SWR issue, no matter how small, it is not 
likely 50 ohms.  And if one uses the transceiver internal ATU to the 
input of the filter, likewise the filter input doesn't see 50 ohms.


Correctly used the bandpass filter must be in the path between the PA 
output and the ATU input.  With an internal ATU, this isn't likely 
possible.


And most filters are designed for a certain power level when operated 
from a source and into a load of 50 ohms.  Should one depart from the 
correct source and load impedance, then the filter my fail due to 
excessive voltage.


If the K3 is seeing an SWR of 2:1 or less, don't bother.  If the 
operator feels good about "touching it up" that is only good for the 
operator.  The radio doesn't care one way of the other.


Use a bandpass filter correctly or don't use one.  For if you do, you'll 
likely let the smoke out of the box.


73

Bob, K4TAX


On 7/5/2019 9:57 AM, Rich wrote:
To minimize emails direct replies would be nice.  I searched the web 
and could not find an answer.   I know there are a ton of smart folks 
on this list so I thought I would ask.

TU
On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then 
using the K3 ant tuner to touch up the SWR between the radio and the 
bandpass filter.  Is that an acceptable practice?


I would think not?

Rich

K3RWN

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Re: [Elecraft] OT a bit: K3 Ant Tuner

[K9MA]

One reason to use the internal ATU with an external tuner is so the 
transmitter can see a low SWR over a range of frequencies, without 
retuning the external filter. Also, if the external tuner can only get 
down to, say 2:1, the internal ATU will get it down to 1:1, and the 
transmitter will be happier.


73,
Scott K9MA



On 7/5/2019 13:20, Mark Goldberg wrote:

I stand corrected.

I made an assumption, probably incorrectly, that the reason they had a
second tuner was that the first did not successfully tune the antenna. They
just decided to put the bandpass filter between the two tuners, which would
have provided a mismatch at both the filter input and output. I just used a
mismatch at the output as an example. I just provided an example of filter
performance degradation with even what would be considered a reasonable SWR.

I prefer Jack's solution of bypassing the internal K3 tuner. I do have a
situation where my antenna tuner can't tune my antenna on 160. Rather than
try to use two tuners in series with the requisite losses, I added a shunt
inductor on a big ferrite core to provide most of the required inductance
for a match. It gets hot.

73,

Mark
W7MLG


On Fri, Jul 5, 2019 at 10:57 AM David Gilbert 
wrote:


I think you misread the situation.  The question isn't whether to put a
single antenna tuner between the antenna and filter versus putting it
between the rig and the filter.  The question is whether putting an
ADDITIONAL tuner (the one internal to the K3) at the input of the filter
is a good idea.  And to me it seems the answer is yes.

I think we all agree that the right feed impedance and load impedance
for a filter is important.  And as I pointed out, not just for power
handling, but also for the filter to actually filter as it was intended.

73,
Dave   AB7E

On 7/5/2019 10:18 AM, Mark Goldberg wrote:

I could not let this go. I've done a lot of work with bandpass filters.

The

mismatch will degrade the filter.

For an example, I used Elsie, which is a filter calculator. Using the
example 20 Meter bandpass filter, the passband loss is about .25 dB with
matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
losses increase to about 0.4 - .44 dB and vary more over the band.

Here are the schematics and plots, anyone is welcome to check my
calculations, as I do make mistakes!



https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing

The loss in the filter will almost double. For 100W in, the loss goes

from

about 6W to about 10W. So, it is not a good idea. A worse match will

result

in even more losses, perhaps overheating and destroying the filter.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm 

wrote:

Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more
loss due to inductor winding resistance, but other than that, it should
do harm.

Several bandpass filters indicate that they should be between the rig
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to
the rig power, then I would observe that caution. Refer to the bandpass
filter specs.

73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:

To minimize emails direct replies would be nice.  I searched the web

and

could not find an answer.   I know there are a ton of smart folks on
this list so I thought I would ask.

On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  -

Antenna

So the antenna was tuned via the external tuner, but saw a guy then
using the K3 ant tuner to touch up the SWR between the radio and the
bandpass filter.  Is that an acceptable practice?







--
Scott  K9MA

k...@sdellington.us

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Re: [Elecraft] OT a bit: K3 Ant Tuner

[K9MA]

On 7/5/2019 12:55, Jack Brindle via Elecraft wrote:

OK, so let’s look at the K3 side. The K3 antenna port connects directly to the 
BPF’s radio port. Again, we are presuming the BPF is designed for 50 ohms 
resistive source/load. The K3 is designed to transmit into a 50 ohm load, but 
it may not itself be a 50 ohm source. And, the receiver input may not be 50 
ohms as well. Adding a tuned ATU does bring this to 50 ohms, providing a proper 
match into the BPF, so that optimum signal flows both ways.


Bandpass filters are generally designed for 50 Ohm source and load 
resistances, mainly because the actual source and load impedances are 
usually unknown. These filters will only perform as advertised with a 50 
Ohm source and load. With real world impedances, you just have to hope 
for the best. It's easy enough to use a tuner or other matching network 
to get the load impedance close to 50 Ohms in the passband, but even 
then, the impedance outside the passband may be far different, so filter 
performance will not match the ideal case. It might be better, or it 
might be worse. Unless you know the actual impedances, you can't predict it.


The source impedance is another matter. The output impedance of a 
transmitter is almost certainly NOT 50 Ohms. It's probably much lower. 
After all, an ideal voltage source has an output impedance of zero, and 
is 100 percent efficient. The ATU matches the LOAD to 50 Ohms, so the 
transmitter sees a 50 Ohm load, but does NOT necessarily match the 
output impedance to 50 Ohms. This is another reason real world filter 
performance almost certainly differs from the ideal. Again, unless you 
know the source and load impedances over the whole range of frequencies 
of interest, you can't predict the filter performance. While it's 
unlikely to happen by accident, it's possible to find a source impedance 
for any reflective filter which will result in zero (or very little) 
attenuation at any frequency. It's called a conjugate match.


In reality, though, we seem to get pretty good results with these 50 Ohm 
filters. You can actually measure the parameters that are really 
important, like harmonic attenuation, and see whether it is good 
enough.  Even then, though, there's uncertainty, as that measurement is 
usually made with a dummy load. What if the impedance of your antenna at 
a harmonic isn't 50 Ohms?


73,

Scott K9MA

--
Scott  K9MA

k...@sdellington.us

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[Elecraft] Follow up on "Digital modes on 144MHz only"

[Kjeld Holm]

Thanks to all who replied to my mail (see below) but allow me to ask: 

Anyone using Elecraft XV144 or K144XV or HG 144-K for digital modes? 

Any comments on these being better or worse than other brands?

Vy 73 de OZ1CCM, Kjeld  

-Original Message-
From: elecraft-boun...@mailman.qth.net 
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Kjeld Holm
Sent: 4. juli 2019 20:31
To: Elecraft Reflector
Subject: [Elecraft] Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you 
look at performance only (no price, no ergonomics, no use outside digital modes 
on 144MHz) what would you prefer

1)   K3/K3S with internal transverter
2)   IC-9700

In both cases I plan to use a 1kW amplifier. 

Vy 73 de OZ1CCM, Kjeld
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[Elecraft] AX1 shipping status

[rich hurd WC3T]

Now it's my turn to mope.   I ordered my AX1 without noticing that it won't
ship until sometime after the 20th. Shame on me for not checking the
web site first.

-- 
72,
Rich Hurd / WC3T / DMR: 3142737
Northampton County RACES, EPA-ARRL Public Information Officer for Scouting
Latitude: 40.761621 Longitude: -75.288988  (40°45.68' N 75°17.33' W) Grid:
*FN20is*
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Mark Goldberg]

I stand corrected.

I made an assumption, probably incorrectly, that the reason they had a
second tuner was that the first did not successfully tune the antenna. They
just decided to put the bandpass filter between the two tuners, which would
have provided a mismatch at both the filter input and output. I just used a
mismatch at the output as an example. I just provided an example of filter
performance degradation with even what would be considered a reasonable SWR.

I prefer Jack's solution of bypassing the internal K3 tuner. I do have a
situation where my antenna tuner can't tune my antenna on 160. Rather than
try to use two tuners in series with the requisite losses, I added a shunt
inductor on a big ferrite core to provide most of the required inductance
for a match. It gets hot.

73,

Mark
W7MLG


On Fri, Jul 5, 2019 at 10:57 AM David Gilbert 
wrote:

>
> I think you misread the situation.  The question isn't whether to put a
> single antenna tuner between the antenna and filter versus putting it
> between the rig and the filter.  The question is whether putting an
> ADDITIONAL tuner (the one internal to the K3) at the input of the filter
> is a good idea.  And to me it seems the answer is yes.
>
> I think we all agree that the right feed impedance and load impedance
> for a filter is important.  And as I pointed out, not just for power
> handling, but also for the filter to actually filter as it was intended.
>
> 73,
> Dave   AB7E
>
> On 7/5/2019 10:18 AM, Mark Goldberg wrote:
> > I could not let this go. I've done a lot of work with bandpass filters.
> The
> > mismatch will degrade the filter.
> >
> > For an example, I used Elsie, which is a filter calculator. Using the
> > example 20 Meter bandpass filter, the passband loss is about .25 dB with
> > matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
> > ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
> > losses increase to about 0.4 - .44 dB and vary more over the band.
> >
> > Here are the schematics and plots, anyone is welcome to check my
> > calculations, as I do make mistakes!
> >
> >
> https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing
> >
> > The loss in the filter will almost double. For 100W in, the loss goes
> from
> > about 6W to about 10W. So, it is not a good idea. A worse match will
> result
> > in even more losses, perhaps overheating and destroying the filter.
> >
> > 73,
> >
> > Mark
> > W7MLG
> >
> > On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm 
> wrote:
> >
> >> Rich,
> >>
> >> Yes and no.  With 2 antenna tuners in-line, there will be a bit more
> >> loss due to inductor winding resistance, but other than that, it should
> >> do harm.
> >>
> >> Several bandpass filters indicate that they should be between the rig
> >> and the tuner (so the bandpass filters are not run at a high SWR).
> >> If the power rating of the bandpass filter is marginal with respect to
> >> the rig power, then I would observe that caution. Refer to the bandpass
> >> filter specs.
> >>
> >> 73,
> >> Don W3FPR
> >>
> >> On 7/5/2019 10:57 AM, Rich wrote:
> >>> To minimize emails direct replies would be nice.  I searched the web
> and
> >>> could not find an answer.   I know there are a ton of smart folks on
> >>> this list so I thought I would ask.
> >>>
> >>> On Field Day at typical setup is :
> >>>
> >>> K3 (or any radio) - bandpass filter -  External Antenna Tuner  -
> Antenna
> >>>
> >>> So the antenna was tuned via the external tuner, but saw a guy then
> >>> using the K3 ant tuner to touch up the SWR between the radio and the
> >>> bandpass filter.  Is that an acceptable practice?
> >>>
> >> __
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> >> Message delivered to marklgoldb...@gmail.com
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> >
>
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Wes]

Good points, some of which I considered making in my last post.  Regarding the 
SWR measurement capabilities of the K3 (or many other devices) I wrote about 
this too in another thread:


http://elecraft.365791.n2.nabble.com/K3-SWR-Numerical-Indication-td7643839.html

Wes  N7WS


On 7/5/2019 10:37 AM, David Gilbert wrote:


It's not just a power issue.  A filter only achieves its design goals if the 
impedance feeding it and the load impedance it sees are as expected.  Most 
filters are going to want to be fed by 50 ohms and see a load of 50 ohms.  
Most rigs (not sure about the K3) don't actually present a pure 50 ohm output 
impedance, so using the internal tuner in the K3 supposedly would assure that 
the filter sees the correct feed impedance, and for an operation like Field 
Day having a properly performing filter might be more important than a bit of 
power loss in the K3 tuner inductor.


On the other hand, I'm not sure that the SWR meter in the K3 is a perfect 
indicator of a match to a 50 ohm load.  I recently did some SWR measurements 
on a new antenna setup for five different bands (three different antennas) 
using four different indicators ... the SWR meter in the K3, an AEA HF-CIA, an 
Elecraft W2, and a new FA-VA5.  All four instruments were located in the same 
spot on the transmission line for each band (I swapped them in and out), and I 
plotted the SWR curves for frequencies across each band band.  The readings 
with the most deviation from the others came from the K3, and for certain 
cable lengths (I did readings with and without an additional 7 foot length of 
feedline inserted) it was significant.


73,
Dave  AB7E



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Re: [Elecraft] OT a bit: K3 Ant Tuner

[David Gilbert]

I think you misread the situation.  The question isn't whether to put a 
single antenna tuner between the antenna and filter versus putting it 
between the rig and the filter.  The question is whether putting an 
ADDITIONAL tuner (the one internal to the K3) at the input of the filter 
is a good idea.  And to me it seems the answer is yes.


I think we all agree that the right feed impedance and load impedance 
for a filter is important.  And as I pointed out, not just for power 
handling, but also for the filter to actually filter as it was intended.


73,
Dave   AB7E

On 7/5/2019 10:18 AM, Mark Goldberg wrote:

I could not let this go. I've done a lot of work with bandpass filters. The
mismatch will degrade the filter.

For an example, I used Elsie, which is a filter calculator. Using the
example 20 Meter bandpass filter, the passband loss is about .25 dB with
matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
losses increase to about 0.4 - .44 dB and vary more over the band.

Here are the schematics and plots, anyone is welcome to check my
calculations, as I do make mistakes!

https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing

The loss in the filter will almost double. For 100W in, the loss goes from
about 6W to about 10W. So, it is not a good idea. A worse match will result
in even more losses, perhaps overheating and destroying the filter.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm  wrote:


Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more
loss due to inductor winding resistance, but other than that, it should
do harm.

Several bandpass filters indicate that they should be between the rig
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to
the rig power, then I would observe that caution. Refer to the bandpass
filter specs.

73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:

To minimize emails direct replies would be nice.  I searched the web and
could not find an answer.   I know there are a ton of smart folks on
this list so I thought I would ask.

On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then
using the K3 ant tuner to touch up the SWR between the radio and the
bandpass filter.  Is that an acceptable practice?


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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Jack Brindle via Elecraft]

Lets step back a bit and look at the system here. The K3, with ATU, drives into 
the BPF, when then drives into the external ATU and finally the antenna.
The external ATU takes care of the antenna matching, and should present a 50 
ohm load to the BPF. The BPF, because of its design, should present a 50 ohm 
load to the ATU as well, so everything is matched there.
Before anyone jumps on this, remember the signals go both ways, outbound for 
transmit, inbound for receive. Also, we have a fundamental principal thrown at 
every EE student, that for best transmission of signal, the source and load 
impedances should match.

OK, so let’s look at the K3 side. The K3 antenna port connects directly to the 
BPF’s radio port. Again, we are presuming the BPF is designed for 50 ohms 
resistive source/load. The K3 is designed to transmit into a 50 ohm load, but 
it may not itself be a 50 ohm source. And, the receiver input may not be 50 
ohms as well. Adding a tuned ATU does bring this to 50 ohms, providing a proper 
match into the BPF, so that optimum signal flows both ways. So it could 
actually be beneficial for the ATU to be in-line and properly tuned. The best 
way to perform the tune would be to tune the ATU into a 50 ohm dummy load, but 
tuning into the BPF at low power should work also. The exception to this would 
be if the BPF changes impedance when power is applied, but then if this happens 
the best place for that BPF is the trash can.

Now having said this, the ATU can also be bypassed in the K3, and that circuit 
may provide a proper 50 ohm source/load for the BPF. I would probably take this 
approach myself (and in fact do so in my station). The reason I take this 
approach is to avoid the small loss that the internal ATU presents. In 
contesting, every db matters.

Note that we are talking nits at this point. Unless the ATU was tuned for a 
load quite a bit off 50 ohms resistive, (quite possible), then retuning won’t 
make much difference. Perhaps the op had this situation, and thought it better 
to return the ATU than to bypass it, or he didn’t even think to bypass it. The 
point is, both methods will work, and I doubt he did anything wrong it 
performing the tune.

73!
Jack, W6FB


> On Jul 5, 2019, at 10:18 AM, Mark Goldberg  wrote:
> 
> I could not let this go. I've done a lot of work with bandpass filters. The
> mismatch will degrade the filter.
> 
> For an example, I used Elsie, which is a filter calculator. Using the
> example 20 Meter bandpass filter, the passband loss is about .25 dB with
> matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
> ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
> losses increase to about 0.4 - .44 dB and vary more over the band.
> 
> Here are the schematics and plots, anyone is welcome to check my
> calculations, as I do make mistakes!
> 
> https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing
> 
> The loss in the filter will almost double. For 100W in, the loss goes from
> about 6W to about 10W. So, it is not a good idea. A worse match will result
> in even more losses, perhaps overheating and destroying the filter.
> 
> 73,
> 
> Mark
> W7MLG
> 
> On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm  wrote:
> 
>> Rich,
>> 
>> Yes and no.  With 2 antenna tuners in-line, there will be a bit more
>> loss due to inductor winding resistance, but other than that, it should
>> do harm.
>> 
>> Several bandpass filters indicate that they should be between the rig
>> and the tuner (so the bandpass filters are not run at a high SWR).
>> If the power rating of the bandpass filter is marginal with respect to
>> the rig power, then I would observe that caution. Refer to the bandpass
>> filter specs.
>> 
>> 73,
>> Don W3FPR
>> 
>> On 7/5/2019 10:57 AM, Rich wrote:
>>> To minimize emails direct replies would be nice.  I searched the web and
>>> could not find an answer.   I know there are a ton of smart folks on
>>> this list so I thought I would ask.
>>> 
>>> On Field Day at typical setup is :
>>> 
>>> K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna
>>> 
>>> So the antenna was tuned via the external tuner, but saw a guy then
>>> using the K3 ant tuner to touch up the SWR between the radio and the
>>> bandpass filter.  Is that an acceptable practice?
>>> 
>> __
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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Wes]

You're offering a scenario different from the original.  As I read it, 
originally a tuner was used to flatten the load that terminates the BPF output.  
Your analysis assumes a matched driver and a mismatch on the output of the BPF.


Then the OP mentioned a second tuner between the TX output and the input of the 
BPF, which can be assumed to match the BPF input.  The BPF is now matched at 
both ends.


To answer the OP's question, the answer is, IMHO of course, yes.

Wes  N7WS

On 7/5/2019 10:18 AM, Mark Goldberg wrote:

I could not let this go. I've done a lot of work with bandpass filters. The
mismatch will degrade the filter.

For an example, I used Elsie, which is a filter calculator. Using the
example 20 Meter bandpass filter, the passband loss is about .25 dB with
matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
losses increase to about 0.4 - .44 dB and vary more over the band.

Here are the schematics and plots, anyone is welcome to check my
calculations, as I do make mistakes!

https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing

The loss in the filter will almost double. For 100W in, the loss goes from
about 6W to about 10W. So, it is not a good idea. A worse match will result
in even more losses, perhaps overheating and destroying the filter.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm  wrote:


Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more
loss due to inductor winding resistance, but other than that, it should
do harm.

Several bandpass filters indicate that they should be between the rig
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to
the rig power, then I would observe that caution. Refer to the bandpass
filter specs.

73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:

To minimize emails direct replies would be nice.  I searched the web and
could not find an answer.   I know there are a ton of smart folks on
this list so I thought I would ask.

On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then
using the K3 ant tuner to touch up the SWR between the radio and the
bandpass filter.  Is that an acceptable practice?


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Re: [Elecraft] OT a bit: K3 Ant Tuner

[David Gilbert]

It's not just a power issue.  A filter only achieves its design goals if 
the impedance feeding it and the load impedance it sees are as 
expected.  Most filters are going to want to be fed by 50 ohms and see a 
load of 50 ohms.  Most rigs (not sure about the K3) don't actually 
present a pure 50 ohm output impedance, so using the internal tuner in 
the K3 supposedly would assure that the filter sees the correct feed 
impedance, and for an operation like Field Day having a properly 
performing filter might be more important than a bit of power loss in 
the K3 tuner inductor.


On the other hand, I'm not sure that the SWR meter in the K3 is a 
perfect indicator of a match to a 50 ohm load.  I recently did some SWR 
measurements on a new antenna setup for five different bands (three 
different antennas) using four different indicators ... the SWR meter in 
the K3, an AEA HF-CIA, an Elecraft W2, and a new FA-VA5.  All four 
instruments were located in the same spot on the transmission line for 
each band (I swapped them in and out), and I plotted the SWR curves for 
frequencies across each band band.  The readings with the most deviation 
from the others came from the K3, and for certain cable lengths (I did 
readings with and without an additional 7 foot length of feedline 
inserted) it was significant.


73,
Dave  AB7E



On 7/5/2019 8:32 AM, Don Wilhelm wrote:

Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more 
loss due to inductor winding resistance, but other than that, it 
should do harm.


Several bandpass filters indicate that they should be between the rig 
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to 
the rig power, then I would observe that caution. Refer to the 
bandpass filter specs.


73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:
To minimize emails direct replies would be nice.  I searched the web 
and could not find an answer.   I know there are a ton of smart folks 
on this list so I thought I would ask.


On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then 
using the K3 ant tuner to touch up the SWR between the radio and the 
bandpass filter.  Is that an acceptable practice?



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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Mark Goldberg]

I could not let this go. I've done a lot of work with bandpass filters. The
mismatch will degrade the filter.

For an example, I used Elsie, which is a filter calculator. Using the
example 20 Meter bandpass filter, the passband loss is about .25 dB with
matched 50 ohms in and out. Changing the output impedance to 38+j12 (38
ohms plus 135 nH inductor at 14.15 MHz, about 1.5:1 SWR), the passband
losses increase to about 0.4 - .44 dB and vary more over the band.

Here are the schematics and plots, anyone is welcome to check my
calculations, as I do make mistakes!

https://drive.google.com/file/d/1kj31IL_px6nVyRadW4nOi_c6FLgyaRyk/view?usp=sharing

The loss in the filter will almost double. For 100W in, the loss goes from
about 6W to about 10W. So, it is not a good idea. A worse match will result
in even more losses, perhaps overheating and destroying the filter.

73,

Mark
W7MLG

On Fri, Jul 5, 2019 at 8:32 AM Don Wilhelm  wrote:

> Rich,
>
> Yes and no.  With 2 antenna tuners in-line, there will be a bit more
> loss due to inductor winding resistance, but other than that, it should
> do harm.
>
> Several bandpass filters indicate that they should be between the rig
> and the tuner (so the bandpass filters are not run at a high SWR).
> If the power rating of the bandpass filter is marginal with respect to
> the rig power, then I would observe that caution. Refer to the bandpass
> filter specs.
>
> 73,
> Don W3FPR
>
> On 7/5/2019 10:57 AM, Rich wrote:
> > To minimize emails direct replies would be nice.  I searched the web and
> > could not find an answer.   I know there are a ton of smart folks on
> > this list so I thought I would ask.
> >
> > On Field Day at typical setup is :
> >
> > K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna
> >
> > So the antenna was tuned via the external tuner, but saw a guy then
> > using the K3 ant tuner to touch up the SWR between the radio and the
> > bandpass filter.  Is that an acceptable practice?
> >
> __
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Re: [Elecraft] Fwd: K4/K4D antenna ports.

[Wayne Burdick]

Nr4c  wrote:


>> How many ports does a K4D have without the ATU. 

1 main antenna jack and 2 receive antenna inputs.


>> 
>> I know the K4 only has one I think the ATU ads 2 more for total of three. 

Yes. Also, any one of the ATU antenna jacks can be designated as a third 
receive antenna input (for either receiver).


>> But K4D must have two ports for separate antennas for Diversity, right?

Yes, RX ANT1 and RX ANT2. The latter is also labeled XVTR IN, and can be used 
with transverters.

73,
Wayne
N6KR

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[Elecraft] Fwd: K4/K4D antenna ports.

[Nr4c]

> From: Nr4c 
> Date: July 4, 2019 at 11:03:45 PM EDT
> To: n...@elecraft.com
> Subject: K4/K4D antenna ports. 
> 
> Wayne. 
> 
> How many ports does a K4D have without the ATU. 
> 
> I know the K4 only has one I think the ATU ads 2 more for total of three. 
> 
> But K4D must have two ports for separate antennas for Diversity, right?
> 
> Sent from my iPhone
> ...nr4c. bill
> 
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Re: [Elecraft] Digital modes on 144MHz only

[Mike Harris via Elecraft]

Our first commercial 11 metre dish earth station built in 1984 had a 
4GHz 60dB gain, 33 Kelvin, electrically cooled two stage parametric LNA 
at the feed horn. the cable to the receive system was LDF4-50 with 20dB 
loss to a six port passive splitter.


The LNAs despite being pressurised constantly with dry air with a small 
bleed hole had to be purged of frost every six months by turning the 
cooling into heating and increasing the outflow of air. After 12 hours 
of cool down they had to be retuned, pump frequency and power to achieve 
60dB flat gain over 500MHz bandwidth. Times have changed.


Regards,

Mike VP8NO

On 05/07/2019 10:08, Wes wrote:
That isn't quite right either.  The preamp gain must be much higher than 
the following losses to minimize second stage degradation. (Line loss 
degrades the NF of the second stage)


Wes  N7WS

On 7/5/2019 5:35 AM, Martin wrote:


That's not quite right. The overall system noise is determined by the 
preamp noise figure when mounted as close  to the antenna as possible. 
Cable losses (=noise) after the preamp can be neglected, as long as 
the gain of the preamp is higher than the losses in subsequent 
components. So the cable AFTER the preamp can be pretty lossy. OTOH, 
too much gain from the preamp easily overdrives your transceiver's RX. 
A good balance between gain vs. cable losses is mandatory. The noise 
figure of the pramp is crucial.
If you are satisfied with your transverter's noise figure , mount it 
close to the antenna via a short run low loss cable, if you can. This 
saves the expenses for a preamp.


This applies to the RX path. I'm not talking cable quality or output 
power for TX.

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[Elecraft] (no subject)

[Edward R Cole]

Kjeld,

I agree with Conrad PA5Y,  both Kuhne Engineering or  HA1YA make very 
good transverters and are available in EU.


I would add the DEMI L-series transverter which now is made by a 
company called Q5 (located in US) for any NA hams reading the mail on 
this topic.
I use DEMI transverters on digital-eme on 144, 1296, and higher (have 
had 144,222, 432, 1296, 3456, and 10-GHz models).


I also use preamps located at antennas on 6m, 2m, 432, 1296+  Even 
though local electronic noise can be high at times, when its not they 
make a huge difference.  Only for 6m (50-MHz) would I agree that it 
might not give much help (but if you have a K3, it needs either a PR6 
or other preamp to bring up 6m &10m sensitivity; not an issue with 
K3s or K4).  MY KX3 with internal preamp ON = my K3 + PR6 in sensitivity on 6m)


The early reports on the IC-9700 were not favorable for freq 
stability (though I read they had addressed this, lately).  Still 
investment in K3s + good transverter will beat the IC-9700 without a doubt.


73, Ed - KL7UW

From: Kjeld Holm 
To: Elecraft Reflector 
Subject: [Elecraft] Digital modes on 144MHz only
Message-ID:



Content-Type: text/plain; charset="us-ascii"

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. 
If you look at performance only (no price, no ergonomics, no use 
outside digital modes on 144MHz) what would you prefer


1)   K3/K3S with internal transverter
2)   IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld


73, Ed - KL7UW
  http://www.kl7uw.com
Dubus-NA Business mail:
  dubus...@gmail.com 


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Re: [Elecraft] When Transmitting on FT8 - KPA500 has issues - KD8ZYD

[David Haines]

I haven't been following this thread closely, but it sounds like what 
has been going on with my K3X with KXPA100 and internal ATU on FT8.


Transmitting with 100w, the relays click rapidly while the power meter 
on the KXPA100  jumps up and down.  Seems to be trying to find a match 
that's not there.  I've been trying different settings and the problem 
goes away when I increase the "power" (audio output) slider on WSJT-X.  
Increasing MIC GAIN and reducing the WSJT-X "power" slider seems to fix 
it too. Does this make sense to anybody?


73, David, KC1DNY

On 7/1/2019 9:26 PM, Fred wrote:


Hi Ken,

It only happens when running digital mode FT8. And it doesn’t happen all the 
time when running digital mode. Ken I’ll send the video I made. I just looked 
at it and it has an *.

Thanks,

Fred
248-613-4086

Sent from my iPhone


On Jul 1, 2019, at 9:22 PM, Ken Winterling  wrote:

Fred,

Does this condition also happen on SSB, RTTY, CW or only while running digital 
mode?

Is it possible the PTT/key line is being dropped?  When the power drops is 
there an asterisk (*) on the left side of the KPA500 display?  An asterisk will 
appear on the left side of the LCD display if there is a valid PA KEY/PTT 
signal is being received from the transceiver. If there is no asterisk the amp 
isn't receiving a valid PA KEY/PTT signal from the transceiver.  If there is an 
underscore instead of an asterisk it means that the amplifier keying is being 
inhibited by a low signal on pin 11 of the AUX connector.

Ken
WA2LBI
  






On Mon, Jul 1, 2019 at 9:06 PM Fred  wrote:
Hi,

I have a K3, P3, KPA500, KAT500 and a SignaLink for sound.  Sometimes when
I transmit on FT8 running full power on the KPA500, the KPA500 will click
on/off.  The power doesn't turn on/off, it seems like a relay inside.  The
power meter will go to about 500 watts, then down to 0, then to abut 500
watts...and down to 0 maybe once a second.  I have a short video I can send
if someone would like to see it.  When I bypass the KPA500 and use 50 watts
or so just on the K3, no issues.

Please let me know if you have any questions.

73, Fred

KD8ZYD
--
Thanks,

Fred


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Re: [Elecraft] OT a bit: K3 Ant Tuner

[Don Wilhelm]

Rich,

Yes and no.  With 2 antenna tuners in-line, there will be a bit more 
loss due to inductor winding resistance, but other than that, it should 
do harm.


Several bandpass filters indicate that they should be between the rig 
and the tuner (so the bandpass filters are not run at a high SWR).
If the power rating of the bandpass filter is marginal with respect to 
the rig power, then I would observe that caution. Refer to the bandpass 
filter specs.


73,
Don W3FPR

On 7/5/2019 10:57 AM, Rich wrote:
To minimize emails direct replies would be nice.  I searched the web and 
could not find an answer.   I know there are a ton of smart folks on 
this list so I thought I would ask.


On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then 
using the K3 ant tuner to touch up the SWR between the radio and the 
bandpass filter.  Is that an acceptable practice?



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[Elecraft] OT a bit: K3 Ant Tuner

[Rich]

To minimize emails direct replies would be nice.  I searched the web and 
could not find an answer.   I know there are a ton of smart folks on 
this list so I thought I would ask.


On Field Day at typical setup is :

K3 (or any radio) - bandpass filter -  External Antenna Tuner  - Antenna

So the antenna was tuned via the external tuner, but saw a guy then 
using the K3 ant tuner to touch up the SWR between the radio and the 
bandpass filter.  Is that an acceptable practice?


I would think not?

Rich

K3RWN

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Re: [Elecraft] KPA 1500 Remote Program V1.27

[rocketnj]

What I would like to see is ability to control amp from a smartphone, either
native app or a web page via login/password. I've been working on the latter
using a Raspberry Pi in the shack talking to the amp via Ethernet. It acts
as a web server. I have the telemetry working now and next step is the
control logic (on/off, oper/stby, fan speed increase/decrease, etc).

See attached picture. This is from a web browser.

Dave wo2x




-Original Message-
From: elecraft-boun...@mailman.qth.net  On
Behalf Of Burl Borcherding
Sent: Tuesday, July 2, 2019 10:18 AM
To: Elecraft@mailman.qth.net
Subject: [Elecraft] KPA 1500 Remote Program V1.27

The new software release V1.27 (6/21/19) will now allow WAN connections to
your KPA 1500 for true remote operations.  You can now get rid of the extra
devices and or computer to control you KPA1500 remotely outside your LAN.
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Re: [Elecraft] CW problem

[Don Wilhelm]

John,

The recommended troubleshooting steps in cases like this is to remove 
everything from the K3 except the power cable and the coax to a dummy load.


With that done, does the problem still appear - if so contact 
supp...@elecraft.com.


If it does not appear, then plug things back in one at a time to see 
which external device is causing the problem.


73,
Don W3FPR

On 7/4/2019 9:34 PM, John and Rita Freitag via Elecraft wrote:

I am trying to run down a CW transmit problem on my K3s. Anytime I change the 
mode from LSB or USB on any band to CW it starts to send a “dit” without 
stopping and I have to halt it by restoring the configuration. This does fix it 
until I try to switch to CW again; and then, the same story.


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Re: [Elecraft] Digital modes on 144MHz only

[Wes]

The OP was talking about 144 MHz.  For weak signal work I can't imagine not 
using a mast-mounted preamp. Even with sub 1 dB NF devices (that we paid dearly 
for when I was on EME) located in the shack, line loss is a killer.


Wes  N7WS

On 7/4/2019 10:01 PM, Jim Brown wrote:
In today's world, a mast-mounted preamp is a waste of effort for the vast 
majority of hams because circuit noise in the receiver is rarely the 
limitation on what we hear.


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Re: [Elecraft] Digital modes on 144MHz only

[Wes]

That isn't quite right either.  The preamp gain must be much higher than the 
following losses to minimize second stage degradation. (Line loss degrades the 
NF of the second stage)


Wes  N7WS

On 7/5/2019 5:35 AM, Martin wrote:


That's not quite right. The overall system noise is determined by the preamp 
noise figure when mounted as close  to the antenna as possible. Cable losses 
(=noise) after the preamp can be neglected, as long as the gain of the preamp 
is higher than the losses in subsequent components. So the cable AFTER the 
preamp can be pretty lossy. OTOH, too much gain from the preamp easily 
overdrives your transceiver's RX. A good balance between gain vs. cable losses 
is mandatory. The noise figure of the pramp is crucial.
If you are satisfied with your transverter's noise figure , mount it close to 
the antenna via a short run low loss cable, if you can. This saves the 
expenses for a preamp.


This applies to the RX path. I'm not talking cable quality or output power for 
TX.



> Message: 15
> Date: Thu, 4 Jul 2019 17:11:58 -0500
> From: Bob McGraw K4TAX 
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] Digital modes on 144MHz only
>
> . Start with a mast mounted low noise preamp, then low loss
> feedline such as 7/8" hard-line, and such. Remember, loss in the
> feedline adds to receiver noise.
> ..
>




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Re: [Elecraft] Digital modes on 144MHz only

[Martin]

That's not quite right. The overall system noise is determined by the 
preamp noise figure when mounted as close  to the antenna as possible. 
Cable losses (=noise) after the preamp can be neglected, as long as the 
gain of the preamp is higher than the losses in subsequent components. 
So the cable AFTER the preamp can be pretty lossy. OTOH, too much gain 
from the preamp easily overdrives your transceiver's RX. A good balance 
between gain vs. cable losses is mandatory. The noise figure of the 
pramp is crucial.
If you are satisfied with your transverter's noise figure , mount it 
close to the antenna via a short run low loss cable, if you can. This 
saves the expenses for a preamp.


This applies to the RX path. I'm not talking cable quality or output 
power for TX.



> Message: 15
> Date: Thu, 4 Jul 2019 17:11:58 -0500
> From: Bob McGraw K4TAX 
> To: elecraft@mailman.qth.net
> Subject: Re: [Elecraft] Digital modes on 144MHz only
>
> . Start with a mast mounted low noise preamp, then low loss
> feedline such as 7/8" hard-line, and such. Remember, loss in the
> feedline adds to receiver noise.
> ..
>


--

Ohne CW ist es nur CB..

73, Martin DM4iM
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Re: [Elecraft] Digital modes on 144MHz only

[Dimitry Borzenko]

Hi All.
Internal transverter possible to use but with external BPF

de 4z5cp



-- Original Message --
From: "Michael Walker" 
To: "Elecraft Reflector" 
Sent: 05.07.2019 14:43:36
Subject: Re: [Elecraft] Digital modes on 144MHz only


Hi

These are the Transverters I use.

Very good quality and they can be 10mhz gps locked.


http://www.q5signal.com/

Mike va3mw


Sent from my iPad


 On Jul 5, 2019, at 7:16 AM, Conrad PA5Y  wrote:

 Neither!


 I would buy a good transverter to use with a K3S. Two obvious choices.


 
https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621

 TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio 
Shop
 shop.kuhne-electronic.com
 Endkundenshop main_nav Produkte Meta-Description



 http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm

 ME2T-PRO3 & ME2HT-PRO3 transverter 
specifications
 www.ha1ya.hu
 • Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 
28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI or 
optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input 
Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power 
Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
 Both of these transverters will outperform the Elecraft transverter with 
respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is 
considerably cheaper and that is what I chose, actually in my case the ME2T XP 
because I need 2 channels for Xpol EME. I have extensively tested all these 
combinations.


 The IC9700 is nice and convenient and quite reasonable but both the TX and RX 
performance is inferior to the K3S with either of the above transverters.


 73


 Conrad PA5Y




 
 From: elecraft-boun...@mailman.qth.net  on behalf 
of Kjeld Holm 
 Sent: 04 July 2019 20:31
 To: Elecraft Reflector
 Subject: [Elecraft] Digital modes on 144MHz only

 Digital modes on 144MHz only

 I plan for a second station to use for digital modes on 144MHz only. If you 
look at performance only (no price, no ergonomics, no use outside digital modes 
on 144MHz) what would you prefer

 1)   K3/K3S with internal transverter
 2)   IC-9700

 In both cases I plan to use a 1kW amplifier.

 Vy 73 de OZ1CCM, Kjeld
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Re: [Elecraft] Digital modes on 144MHz only

[Michael Walker]

Hi

These are the Transverters I use. 

Very good quality and they can be 10mhz gps locked. 


http://www.q5signal.com/

Mike va3mw


Sent from my iPad

> On Jul 5, 2019, at 7:16 AM, Conrad PA5Y  wrote:
> 
> Neither!
> 
> 
> I would buy a good transverter to use with a K3S. Two obvious choices.
> 
> 
> https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621
> 
> TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio 
> Shop
> shop.kuhne-electronic.com
> Endkundenshop main_nav Produkte Meta-Description
> 
> 
> 
> http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm
> 
> ME2T-PRO3 & ME2HT-PRO3 transverter 
> specifications
> www.ha1ya.hu
> • Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 
> 28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI 
> or optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input 
> Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power 
> Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
> Both of these transverters will outperform the Elecraft transverter with 
> respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is 
> considerably cheaper and that is what I chose, actually in my case the ME2T 
> XP because I need 2 channels for Xpol EME. I have extensively tested all 
> these combinations.
> 
> 
> The IC9700 is nice and convenient and quite reasonable but both the TX and RX 
> performance is inferior to the K3S with either of the above transverters.
> 
> 
> 73
> 
> 
> Conrad PA5Y
> 
> 
> 
> 
> 
> From: elecraft-boun...@mailman.qth.net  on 
> behalf of Kjeld Holm 
> Sent: 04 July 2019 20:31
> To: Elecraft Reflector
> Subject: [Elecraft] Digital modes on 144MHz only
> 
> Digital modes on 144MHz only
> 
> I plan for a second station to use for digital modes on 144MHz only. If you 
> look at performance only (no price, no ergonomics, no use outside digital 
> modes on 144MHz) what would you prefer
> 
> 1)   K3/K3S with internal transverter
> 2)   IC-9700
> 
> In both cases I plan to use a 1kW amplifier.
> 
> Vy 73 de OZ1CCM, Kjeld
> __
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Re: [Elecraft] Digital modes on 144MHz only

[Conrad PA5Y]

Neither!


I would buy a good transverter to use with a K3S. Two obvious choices.


https://shop.kuhne-electronic.com/kuhne/en/shop/converter-transverte/transverter/TR+144++PRO++Transverter/?card=1621

TR 144 - PRO, Transverter - Kuhne Electronic Amateur Radio 
Shop
shop.kuhne-electronic.com
Endkundenshop main_nav Produkte Meta-Description



http://www.ha1ya.hu/htmkepek/me2t_pro3_spec.htm

ME2T-PRO3 & ME2HT-PRO3 transverter 
specifications
www.ha1ya.hu
• Frequency Coverage: 144.0-146.0MHz band. • IF in/out Frequency : 
28.0-30.0MHz, or 14.0-16.0MHz • LO frq stability: Low phase noise, 1ppm PDI or 
optional 0.5ppm AXTAL TCXO's! • I/O Impedance : 50 Ohm unbalanced • Input 
Voltage : 13.8VDC, +-5%, polarity mismatch, 10A -40dB EMI filter. • Power 
Consumption : 0.55A on RX, 5.5A on TX @30W out version, 10.5A @50W version.
Both of these transverters will outperform the Elecraft transverter with 
respect to TX PN, IMD and RX IMD. They are both excellent, the HA1YA is 
considerably cheaper and that is what I chose, actually in my case the ME2T XP 
because I need 2 channels for Xpol EME. I have extensively tested all these 
combinations.


The IC9700 is nice and convenient and quite reasonable but both the TX and RX 
performance is inferior to the K3S with either of the above transverters.


73


Conrad PA5Y





From: elecraft-boun...@mailman.qth.net  on 
behalf of Kjeld Holm 
Sent: 04 July 2019 20:31
To: Elecraft Reflector
Subject: [Elecraft] Digital modes on 144MHz only

Digital modes on 144MHz only

I plan for a second station to use for digital modes on 144MHz only. If you 
look at performance only (no price, no ergonomics, no use outside digital modes 
on 144MHz) what would you prefer

1)   K3/K3S with internal transverter
2)   IC-9700

In both cases I plan to use a 1kW amplifier.

Vy 73 de OZ1CCM, Kjeld
__
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Re: [Elecraft] CW problem

[Michael Walker]

Good morning 

Do you have any external programs connected via CAT control?

Mike va3mw

Sent from my iPad

> On Jul 5, 2019, at 6:58 AM, Roy Koeppe  wrote:
> 
> John, I think you may have won the Unique Problem Award with that one. Good 
> luck (sorry).
> 
> Roy K6XK
> 
> 
> I am trying to run down a CW transmit problem on my K3s. Anytime I change the 
> mode from LSB or USB on any band to CW it starts to send a “dit” without 
> stopping and I have to halt it by restoring the configuration. This does fix 
> it until I try to switch to CW again; and then, the same story.
> 
> I recently removed a Kent (straight key plug) and the problem showed up. Any 
> ideas?
> 
>John Freitag, WW4JF
> 
> 
> 
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Re: [Elecraft] CW problem

[Roy Koeppe]

John, I think you may have won the Unique Problem Award with that one. Good 
luck (sorry).


Roy K6XK


I am trying to run down a CW transmit problem on my K3s. Anytime I change 
the mode from LSB or USB on any band to CW it starts to send a “dit” without 
stopping and I have to halt it by restoring the configuration. This does fix 
it until I try to switch to CW again; and then, the same story.


I recently removed a Kent (straight key plug) and the problem showed up. Any 
ideas?


John Freitag, WW4JF



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Re: [Elecraft] The ERR 12V Message Question

[Bill Stravinsky via Elecraft]

 The problem is in the male and female connectors.  I don't think a shorter 
power cable will do anything.  There is no substitute for replacing the 
connectors.When I had mine act up Elecraft sent me the wrong parts.  I had a 
contest coming up and wouldn't have enough time to get the correct parts.  I 
took the boardout and cleaned the pins (you could see they were discolored and 
needed replacing).
That worked for the upcoming contest and didn't fail all weekend and for 2 or 3 
more weeks then the ERR 12v fault returned.  I had received the correct 
partsshortly after the contest weekend and did the replacement.  All has been 
fine since.  That was almost two years ago.
BillK3WJV
p.s.  The complete repair took a lot less time than I thought, an afternoon as 
I recall.

On Wednesday, July 3, 2019, 12:43:08 PM EDT, Drew AF2Z  
wrote:  
 
 It's been a while since I did mine but I think disassembly/reassembly 
was a significant part of the effort. I did the front panel connector at 
the same time as the power connector. The actual removal of the 
connectors and soldering new ones went pretty quickly. I'm not sure I'd 
want to go through the disassembly for a "quick fix" only to have to do 
it again in another month.

You might want to refer to online blogs about the process, or Youtube 
videos (if any). Sorry, I don't have the links, but one hint: after you 
snip the connectors off the board use an alligator clip to grasp the pin 
stubs for desoldering; it's easier than trying to manage it with a pair 
of dikes.

73,
Drew
AF2Z



On 07/02/19 21:07, Joseph M. Durnal wrote:
> I'm not sure if I am experiencing the KPA3 power connector issue or
> not.  I've gotten the ERR 12V message twice today.  Powering the K3
> off and on again will clear the message, but it came back, but cleared
> again after a power cycle.
> 
> And, as I type this while transmitting some FT8 in the background, it
> gave me the error message again.  The full Elecraft K3  KPA3 Power
> Connector Replacement  procedure looks like something I won't have
> time to do until next month, is there a quick bandaid I an try until
> then?  Also, is it safe to use the K3 at 10 watts until I get it
> fixed?
> 
> Thanks & 73 de Joseph M. Durnal - NE3R
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