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normal K3 voltage drop on TX

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Charles Yahrling

normal K3 voltage drop on TX

What would be a normal value on the FP voltage display when tx at 100W,
using factory fused cables? No sub installed.

PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
for 17-22A tx @100W.

I suspect bad pass transistor and/or high drop over fuses, but want to
establish normal indication for tx drop. 11.1v seems way out.

tnx in advance

--
de AB1VL
NAQCC #6799

ab1vl.com
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Jerry Moore

Re: normal K3 voltage drop on TX

If you google around you'll find the Astron VS-35M is known to have issues
with voltage sag under load.

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of
Charles Yahrling
Sent: Friday, August 21, 2015 11:06 AM
To: [hidden email]
Subject: [Elecraft] normal K3 voltage drop on TX

What would be a normal value on the FP voltage display when tx at 100W,
using factory fused cables? No sub installed.

PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
for 17-22A tx @100W.

I suspect bad pass transistor and/or high drop over fuses, but want to
establish normal indication for tx drop. 11.1v seems way out.

tnx in advance

--
de AB1VL
NAQCC #6799

ab1vl.com
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Chester Alderman

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

I just quickly tested my K3 s/n 8895 at 100w output into a 52 ohm dummy
load. Key up = 13.5 vDC; Key down = 21.6 vDC. My power cable between my K3
and the Astron 75 amp power supply is homemade #8 twin wire about 8' long.

73,
Tom - W4BQf

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of
Charles Yahrling
Sent: Friday, August 21, 2015 11:06 AM
To: [hidden email]
Subject: [Elecraft] normal K3 voltage drop on TX

What would be a normal value on the FP voltage display when tx at 100W,
using factory fused cables? No sub installed.

PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
for 17-22A tx @100W.

I suspect bad pass transistor and/or high drop over fuses, but want to
establish normal indication for tx drop. 11.1v seems way out.

tnx in advance

--
de AB1VL
NAQCC #6799

ab1vl.com
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hb9brj

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

Same PS here, but a RigRunner 4005 in between PS and K3.

RX 13.5V @ 1.26A
TX (100W CW) 12.0V @ 17A

This yields a resistance of 95mOhms which I consider ok.

73, Markus HB9BRJ

W1KSZ

Re: normal K3 voltage drop on TX

In reply to this post by Jerry Moore

It also depends on the wire size and length of run.
If you get a supply with Sense Terminals you can eliminate that problem.

73, Dick, W1KSZ

On 8/21/2015 8:12 AM, Jerry Moore wrote:

> If you google around you'll find the Astron VS-35M is known to have issues
> with voltage sag under load.
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of
> Charles Yahrling
> Sent: Friday, August 21, 2015 11:06 AM
> To: [hidden email]
> Subject: [Elecraft] normal K3 voltage drop on TX
>
> What would be a normal value on the FP voltage display when tx at 100W,
> using factory fused cables? No sub installed.
>
> PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
> drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
> for 17-22A tx @100W.
>
> I suspect bad pass transistor and/or high drop over fuses, but want to
> establish normal indication for tx drop. 11.1v seems way out.
>
> tnx in advance
>
> --
> de AB1VL
> NAQCC #6799
>
> ab1vl.com
> ______________________________________________________________
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Steve Glickstein

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

Charles, at 100w into a dummy loadI see a .8 volt drop from 13.8 vdc on
a switching supply, and 17.5 amps. I think it may be time for me to
clean some contacts, too. The fuse holders are always good suspects.

73, W4FMD

On 8/21/2015 11:06 AM, Charles Yahrling wrote:

> What would be a normal value on the FP voltage display when tx at 100W,
> using factory fused cables? No sub installed.
>
> PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
> drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
> for 17-22A tx @100W.
>
> I suspect bad pass transistor and/or high drop over fuses, but want to
> establish normal indication for tx drop. 11.1v seems way out.
>
> tnx in advance
>

Chester Alderman

FW: normal K3 voltage drop on TX

In reply to this post by Chester Alderman

ERROR!!

I think it would be closer to correct if my "Key down" statement would have
read "Key down = 12.6 vDC"!! Sorry for the error!

73,
Tom - W4BQF

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of
Chester Alderman
Sent: Friday, August 21, 2015 11:23 AM
To: 'Charles Yahrling'; [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX

I just quickly tested my K3 s/n 8895 at 100w output into a 52 ohm dummy
load. Key up = 13.5 vDC; Key down = 21.6 vDC. My power cable between my K3
and the Astron 75 amp power supply is homemade #8 twin wire about 8' long.

73,
Tom - W4BQf

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of
Charles Yahrling
Sent: Friday, August 21, 2015 11:06 AM
To: [hidden email]
Subject: [Elecraft] normal K3 voltage drop on TX

What would be a normal value on the FP voltage display when tx at 100W,
using factory fused cables? No sub installed.

PS is Astron VS-35M linear, voltage set at 13.9 idling per FP display.
drops to 11.1 on TX. Current varies but up to 15.5A indicated. Specs call
for 17-22A tx @100W.

I suspect bad pass transistor and/or high drop over fuses, but want to
establish normal indication for tx drop. 11.1v seems way out.

tnx in advance

--
de AB1VL
NAQCC #6799

ab1vl.com
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Joe Subich, W4TV-4

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

On 8/21/2015 11:06 AM, Charles Yahrling wrote:
> What would be a normal value on the FP voltage display when tx at
> 100W, using factory fused cables? No sub installed.

I don't know about "factory fused cables" since my factory cable does
not have fuses. However, using the stock cable and an Astron RS-35A,
My K3 reads 13.8V in receive, 12.9V in transmit with 17.9A for 105 W
output into a dummy load on 20 meters.

I would be very uncomfortable with an indicated 2V drop under load
as that indicates more than 0.1 Ohm of resistance in connectors,
fuses and cable.

What voltage does the RS-35M front panel meter show under load? If
it also sags, your problem could be pass transistor or internal
connections (e.g. loose screws on the filter capacitor). If it is
steady, your problem is in the cable/fuses/etc.

73,

... Joe, W4TV

On 8/21/2015 11:06 AM, Charles Yahrling wrote:

Richard S. Leary

Re: normal K3 voltage drop on TX

In reply to this post by hb9brj

PS here is Astron RS-35M, connected directly to K3/100 #4497. Xmit into 50W
dummy load
RX 13.9V @ 1.15A
TX (100W CW) 12.6V @ 19.62A
Readings from K3 VFO "B" display of "V" and "A"
73, Rick W7LKG

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of hb9brj
Sent: Friday, August 21, 2015 08:23
To: [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX

Same PS here, but a RigRunner 4005 in between PS and K3.

RX 13.5V @ 1.26A
TX (100W CW) 12.0V @ 17A

This yields a resistance of 95mOhms which I consider ok.

73, Markus HB9BRJ

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Jim Brown-10

Re: normal K3 voltage drop on TX

On Fri,8/21/2015 11:52 AM, Richard S. Leary wrote:
> RX 13.9V @ 1.15A
> TX (100W CW) 12.6V @ 19.62A
> Readings from K3 VFO "B" display of "V" and "A"

The difference includes the IR drop in the red/black power cable between
the power supply and the K3. Some quick arithmetic. #10 AWG is 1
milliOhm per foot. A 6 ft cable would be 12 m Ohms (two conductors), so
.216V drop at 18A. With #12, it's .35 volts, .54 volts. Subtract the
numbers for your cable (factoring in the length) from the difference,
and that's the sag in power supply (and, of course, resistance internal
to the K3).

A better way to measure the sag in the PSU is with a digital voltmeter
connected across it's output terminals.

73, Jim K9YC
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Elecraft mailing list

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

Hi All

From my time working in a Ham repair shop I can say that if a power supply dipped by more than 0.25 Volts between RX and 100w TX AT THE TERMINALS ON THE CASE OF THE POWER SUPPLY then that power supply wanted either replacement or repair.

I have just checked my own power supply for my K3 ( EP-925 or PS-30M badged linear PSU) and the voltage change (at the terminals on the case of the power supply) between RX and 100W TX is less than 70 milli-volts. This was measured using a both a Thurlby 1503HA (32000 count) or Fluke 8060A (4.5 digits) meters.

The K3 is fed via 6 feet of 20 Amp cable and shows a voltage change between RX and 100w TX (on the K3 display) of no more than 0.6 Volts. There are no fuses in this lead but if there were I would allow an extra 0.1 volt per fuse giving a total of 0.8 volts. If the k3 showed a difference of 1 volt or more then that would be cause for immediate investigation.

Put in its simplest form a voltage drop of 1 volt at 20 amps means that 20 watts of power is being wasted. In the example quoted by the original author we are seeing a drop of 3 volts at 17-.5 Amps a loss of over 50 watts (the equivalent of 4 Amps at 12.5 Volts)!

Even the cheapest digital meters have a 200 milli-volt range and you can use this to measure the voltage drop across each junction in the wiring to find where the fault lies.

I have cured many rigs that use the standard 6 pin connector of various problems simply by cleaning the power supply lead contacts throughout including the contacts between spade terminals and fuses and fuse holders and fuses.

As a matter of standard practice all my crimp contact junctions are soldered as well as being crimped using a good quality tool.

I hope this note provides adequate guidance.

Regards

Malcolm
G0MIC

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Bob McGraw - K4TAX

Re: normal K3 voltage drop on TX

Malcolm brings up a very good point. All connections should be fitted
with a proper lug which is crimped with a proper tool, depending on wire
size and the terminal to which it will be attached, AND all terminals
should be soldered. I make no exceptions to this practice. The
crimp connection is a mechanical connection, the soldering is the
electrical connection.

One additional point I've found to be most beneficial is to run a
dedicated ground wire between the ground terminal on the radio to the
ground terminal on the power supply. I do not rely on the DC negative
to serve as ground between the radio and power supply.

73
Bob, K4TAX
K3S s/n 10,163

On 8/21/2015 7:45 PM, Malcolm via Elecraft wrote:

> Hi All
>
>
> As a matter of standard practice all my crimp contact junctions are soldered as well as being crimped using a good quality tool.
>
> I hope this note provides adequate guidance.
>
> Regards
>
> Malcolm
> G0MIC
>
>

Jerry Moore

Re: normal K3 voltage drop on TX

I respectfully disagree. A properly made crimp is superior to a soldered
connection. The key word being properly made. If you don't have the correct
tools to do a proper crimp then a good compromise is to solder the connection
after crimping, however, that's only to comply with connection best practice to
establish a good mechanical and electrical connection. A proper crimp serves to
mechanically weld the conductors together.
Jer, AE4PB
K3S TBA

> On August 21, 2015 at 9:20 PM Bob McGraw - K4TAX <[hidden email]> wrote:
>
>
> Malcolm brings up a very good point. All connections should be fitted
> with a proper lug which is crimped with a proper tool, depending on wire
> size and the terminal to which it will be attached, AND all terminals
> should be soldered. I make no exceptions to this practice. The
> crimp connection is a mechanical connection, the soldering is the
> electrical connection.
>
> One additional point I've found to be most beneficial is to run a
> dedicated ground wire between the ground terminal on the radio to the
> ground terminal on the power supply. I do not rely on the DC negative
> to serve as ground between the radio and power supply.
>
> 73
> Bob, K4TAX
> K3S s/n 10,163
>
> On 8/21/2015 7:45 PM, Malcolm via Elecraft wrote:
> > Hi All
> >
> >
> > As a matter of standard practice all my crimp contact junctions are soldered
> > as well as being crimped using a good quality tool.
> >
> > I hope this note provides adequate guidance.
> >
> > Regards
> >
> > Malcolm
> > G0MIC
> >
> >
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
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> Message delivered to [hidden email]

Bob McGraw - K4TAX

Re: normal K3 voltage drop on TX

Properly it must be crimped A N D soldered. Both are required.
Are you saying a crimped and soldered connection is worse than a crimped
only connection?

My military experience says there first must be a mechanical connection
made {crimp or wrap} and then follow with an electrical connection
{solder}. And RCA stipulated this practice in all of their broadcast
equipment.

73
Bob, K4TAX
K3S s/n 10,163

On 8/21/2015 8:38 PM, Jerry Moore wrote:

> I respectfully disagree. A properly made crimp is superior to a
> soldered connection. The key word being properly made. If you don't
> have the correct tools to do a proper crimp then a good compromise is
> to solder the connection after crimping, however, that's only to
> comply with connection best practice to establish a good mechanical
> and electrical connection. A proper crimp serves to mechanically weld
> the conductors together.
> Jer, AE4PB
> K3S TBA
>
> > On August 21, 2015 at 9:20 PM Bob McGraw - K4TAX
> <[hidden email]> wrote:
> >
> >
> > Malcolm brings up a very good point. All connections should be fitted
> > with a proper lug which is crimped with a proper tool, depending on
> wire
> > size and the terminal to which it will be attached, AND all terminals
> > should be soldered. I make no exceptions to this practice. The
> > crimp connection is a mechanical connection, the soldering is the
> > electrical connection.
> >
> > One additional point I've found to be most beneficial is to run a
> > dedicated ground wire between the ground terminal on the radio to the
> > ground terminal on the power supply. I do not rely on the DC negative
> > to serve as ground between the radio and power supply.
> >
> > 73
> > Bob, K4TAX
> > K3S s/n 10,163
> >
> > On 8/21/2015 7:45 PM, Malcolm via Elecraft wrote:
> > > Hi All
> > >
> > >
> > > As a matter of standard practice all my crimp contact junctions
> are soldered as well as being crimped using a good quality tool.
> > >
> > > I hope this note provides adequate guidance.
> > >
> > > Regards
> > >
> > > Malcolm
> > > G0MIC
> > >
> > >
> >
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:[hidden email]
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > Message delivered to [hidden email]

Chester Alderman

Re: normal K3 voltage drop on TX

In reply to this post by Jerry Moore

You should be sure to NEVER say that around a microwave person! As long as
you stay in HF, crimps may be OK. As a retired microwave circuit and systems
design engineer, there will never be a crimped anything in my ham station.
Saying 'crimped' is better than soldered is the same as saying you don't
know what you are talking about! Just my opinion of course.

73,
Tom - W4BQF

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Jerry
Moore
Sent: Friday, August 21, 2015 9:38 PM
To: Bob McGraw - K4TAX; [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX

I respectfully disagree. A properly made crimp is superior to a soldered
connection. The key word being properly made. If you don't have the correct
tools to do a proper crimp then a good compromise is to solder the
connection after crimping, however, that's only to comply with connection
best practice to establish a good mechanical and electrical connection. A
proper crimp serves to mechanically weld the conductors together.
Jer, AE4PB
K3S TBA

his email list: http://www.qsl.net/donate.html Message delivered to
[hidden email]

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Ken G Kopp

Re: normal K3 voltage drop on TX

Tom is correct !

OT Trivia: PL-259's and SO-239's were not designed to be 50 ohms and
seldom are. Use them in impedence-critical situations ... phasing lines,
power dividers, wattmeters, etc. ... at one's own peril. (;-)

73

Ken - K0PP
On Aug 21, 2015 9:01 PM, "Chester Alderman" <[hidden email]>
wrote:

> You should be sure to NEVER say that around a microwave person! As long as
> you stay in HF, crimps may be OK. As a retired microwave circuit and
> systems
> design engineer, there will never be a crimped anything in my ham station.
> Saying 'crimped' is better than soldered is the same as saying you don't
> know what you are talking about! Just my opinion of course.
>
> 73,
> Tom - W4BQF
>
>
>
> -----Original Message-----
> From: Elecraft [mailto:[hidden email]] On Behalf Of
> Jerry
> Moore
> Sent: Friday, August 21, 2015 9:38 PM
> To: Bob McGraw - K4TAX; [hidden email]
> Subject: Re: [Elecraft] normal K3 voltage drop on TX
>
> I respectfully disagree. A properly made crimp is superior to a soldered
> connection. The key word being properly made. If you don't have the correct
> tools to do a proper crimp then a good compromise is to solder the
> connection after crimping, however, that's only to comply with connection
> best practice to establish a good mechanical and electrical connection. A
> proper crimp serves to mechanically weld the conductors together.
> Jer, AE4PB
> K3S TBA
>
>
>
> his email list: http://www.qsl.net/donate.html Message delivered to
> [hidden email]
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>

ktalbott

Re: normal K3 voltage drop on TX

Properly crimped, gas tight connection is superior to solder from DC to
daylight. Just my opinion of course. Oh, and 40 years of experience.
Ken - ke4rg

When the debate is lost, slander becomes the tool of the loser. Socrates

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Ken G
Kopp
Sent: Friday, August 21, 2015 11:16 PM
To: Chester Alderman; [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX

Tom is correct !

OT Trivia: PL-259's and SO-239's were not designed to be 50 ohms and seldom
are. Use them in impedence-critical situations ... phasing lines, power
dividers, wattmeters, etc. ... at one's own peril. (;-)

73

Ken - K0PP
On Aug 21, 2015 9:01 PM, "Chester Alderman" <[hidden email]>
wrote:

> You should be sure to NEVER say that around a microwave person! As
> long as you stay in HF, crimps may be OK. As a retired microwave
> circuit and systems design engineer, there will never be a crimped
> anything in my ham station.
> Saying 'crimped' is better than soldered is the same as saying you
> don't know what you are talking about! Just my opinion of course.
>
> 73,
> Tom - W4BQF
><snip>

Edward R Cole

Re: normal K3 voltage drop on TX

In reply to this post by Charles Yahrling

I agree with Bob, but as 45-years experience has taught me.

Properly crimped bright new copper wire is fine. Take a look several
years later (also compare contact resistance; probably best measured
as voltage drop under load). If you live in the desert where
humidity never rises above 25% you may not see any change. Put the
same crimped connector 100-foot from salt water and less than three
years it will turn green and start to fail. Put on a boat with no
sealant and the connector will fall apart.

Solder the connector after crimping to that bright new copper wire
and those problems will be lessened. ON a boat only airtight sealant
will ensure long life. I find where I want to ensure lowest contact
resistance soldering after crimping works.

But if the wire is subject to repeated movement or vibrational forces
the soldered connection will break whereas crimp-only seems more
resilient. Spacecraft use crimped-only connectors (subject to high
g-force vibration in launch and extreme temperature variations). But
then there is no air in space and thus no moisture to corrode.

For ordinary shack wiring of a ham station crimp+ solder causes no
harm. I use it where ever I want to ensure the lowest voltage drop under load.

Most of those NAPA wire crimpers are a poor excuse for a real tool -
but probably what most of us use. My coax crimpers are properly
racheting crimpers and produce a good contact. Still I do not like
them in situations where the cable sees a lot of movement. Good old
compression back nut construction is best. I'm talking about N, BNC,
TNC, sma, 7/16, etc. PL-259's are used only if I have to.

73, Ed - KL7UW

----------
From: Bob McGraw - K4TAX <[hidden email]>
To: Jerry Moore <[hidden email]>, [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=utf-8; format=flowed

Properly it must be crimped A N D soldered. Both are required.
Are you saying a crimped and soldered connection is worse than a crimped
only connection?

My military experience says there first must be a mechanical connection
made {crimp or wrap} and then follow with an electrical connection
{solder}. And RCA stipulated this practice in all of their broadcast
equipment.

73
Bob, K4TAX
K3S s/n 10,163

73, Ed - KL7UW
http://www.kl7uw.com
"Kits made by KL7UW"
Dubus Mag business:
[hidden email]

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Jerry Moore

Re: normal K3 voltage drop on TX

In reply to this post by Bob McGraw - K4TAX

Guys, there may be new/better information out there, and I’m agreeable to be wrong.

I just know that our Government spends millions/billions to over research everything. What follows is excerpts from the US Navy Electricity and Electronics Training Series, Module 4, Chapter and page is included as reference.

The format of the reference: <chapter>-<page>

2-11 - The increased use of crimp-on terminals is due to the limitations of soldered terminals. The quality

of soldered connections depends mostly upon the operator's skill. Other factors, such as temperature, flux,

cleanliness, oxides, and insulation damage due to heat, also add to defective connections. Solder-type

connections are covered later in this chapter.

An advantage of the crimp-on solderless terminal lugs is that they require relatively little operator

skill to use. Another advantage is that the only tool needed is the crimping tool. This allows terminal lugs

to be applied with a minimum of time and effort. The connections are made rapidly, are clean, and

uniform in construction. Because of the pressures exerted and the material used, the crimped connection

or splice, properly made, is both mechanically and electrically sound.

My comments: I wasn’t able to find the “limitations of soldered terminals” listed. My best guess is that the limits are more based on correct process/skill at the onset to prevent cold joints AND loss of wire flexibility near the connection. The loss of flexibility potentially being more susceptible to weakening/breaks due to vibration – conjecture on my part.

2-24 - Do not tin wires that are to be crimped to

solderless terminals or splices.

I found a source for the modules online - http://jacquesricher.com/NEETS/

Jerry Moore

AE4PB, K3S soon

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Jerry Moore

Re: normal K3 voltage drop on TX

In reply to this post by Chester Alderman

Fair enough Tom :) ,
I've not had the pleasure of doing microwave other than
fixing/troubleshooting radar (APS 180/APS 80). My Navy training didn't
include soldering/crimping for radar other than cannon/other connections.
It's been a long time and I don't recall the magnetron connection types as
we generally would only replace crystals or the whole unit if there was an
issue. I did get to change a waveguide and test it with a sweep cart once.
That was a lot of fun.

-----Original Message-----
From: Chester Alderman [mailto:[hidden email]]
Sent: Friday, August 21, 2015 11:01 PM
To: 'Jerry Moore'; [hidden email]
Subject: RE: [Elecraft] normal K3 voltage drop on TX

You should be sure to NEVER say that around a microwave person! As long as
you stay in HF, crimps may be OK. As a retired microwave circuit and systems
design engineer, there will never be a crimped anything in my ham station.
Saying 'crimped' is better than soldered is the same as saying you don't
know what you are talking about! Just my opinion of course.

73,
Tom - W4BQF

-----Original Message-----
From: Elecraft [mailto:[hidden email]] On Behalf Of Jerry
Moore
Sent: Friday, August 21, 2015 9:38 PM
To: Bob McGraw - K4TAX; [hidden email]
Subject: Re: [Elecraft] normal K3 voltage drop on TX

I respectfully disagree. A properly made crimp is superior to a soldered
connection. The key word being properly made. If you don't have the correct
tools to do a proper crimp then a good compromise is to solder the
connection after crimping, however, that's only to comply with connection
best practice to establish a good mechanical and electrical connection. A
proper crimp serves to mechanically weld the conductors together.
Jer, AE4PB
K3S TBA

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