Does the K3(S) need occasional realignment?

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Does the K3(S) need occasional realignment?

ab2tc
Hi,

Very recently there was the same question asked about the K1. I don't recall
any mention of this topic on the K3 on the reflector. It has internal
trimmers on the per ham band HF filter. Is it advisable to occasionally
touch these up? I have no reason to believe that my oldest K3 (ser#82) is
out of alignment, but I'd like to be ahead of the game. I am old enough to
have used tube rigs in my early ham career and they definitely needed
occasional tune up. The narrow band ham band RF filters in the K3 have
relatively high Q so the slightest component drift will quickly affect the
shape of the filter curve.

If the answer is affirmative, could we get a procedure for doing it
properly? Tuning for max signal at the center frequency may not produce the
proper shape of the bandpass filter (flat top for the required bandwidth). I
know from my previous career as an RF engineer that tuning LC bandpass
filters can be tricky.

AB2TC - Knut




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Re: Does the K3(S) need occasional realignment?

Bob McGraw - K4TAX
While repairing  quite a number of ham radios for others over the years,
I've made a tidy bit of money repairing radios where hams thought they
needed "touching up" with regard to alignments.  {If it isn't broke,
don't try to fix it.}

First, one should use some means and related test and measurement
equipment to determine "if a radio needs alignment".   In other words,
if one can't determine if it needs alignment, it probably does not need
alignment.   Just to jump in an start tweaking coils and trimmers has
put a lot of money in my pocket.  [In fact, I purchased a new loaded K3S
with other hams money. :-) ]

Just a word for the wise.......... I have radios which are 20 to 30
years old which haven't been aligned since ex-factory.  They still meet
specs and thus do not need alignment today.   Now, if one has replaced
parts due to a failure, one should determine if any alignment is
required and if so, proceed.   Just be sure you have correct procedures
and required and calibrated test equipment.

73

Bob, K4TAX



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Re: Does the K3(S) need occasional realignment?

Grant Youngman-2
In reply to this post by ab2tc
I”d be really surprised if this were a “routine maintenance” item.  There probably aren’t more than a handful of people on the reflector that have the necessary equipment and expertise to do it themselves.   And that would mean that Elecraft would get every K3/s back periodically for routine adjustment.  Doesn’t seem reasonable at all.

Tuning at the “center” will NOT produce a proper shape, guaranteed. And peaking the lower and upper pass frequencies aren’t likely to get it “flat” either.   It’s not exceptionally difficult, but you have to know what you’re doing AND have the proper (good) lab equipment.  Most don’t, on either count.  I suspect putting out instructions for a DIY approach to this would be a disaster waiting to happen, given the typical ham shack penchant for “tightening all the screws”  :-)

Grant NQ5T
K3 #2091, KX3 #8342

>
> [The K3} has internal
> trimmers on the per ham band HF filter. Is it advisable to occasionally
> touch these up? I have no reason to believe that my oldest K3 (ser#82) is
> out of alignment, but I'd like to be ahead of the game. I am old enough to
> have used tube rigs in my early ham career and they definitely needed
> occasional tune up. The narrow band ham band RF filters in the K3 have
> relatively high Q so the slightest component drift will quickly affect the
> shape of the filter curve.
>
> If the answer is affirmative, could we get a procedure for doing it
> properly?
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Re: Does the K3(S) need occasional realignment?

ab2tc
In reply to this post by Bob McGraw - K4TAX
Hi Bob and all,

Thanks for your reply. I certainly have no intention to hop in there and
misalign my radio, so this is why I asked. If you encounter a misaligned K3
in your repair activities, how do you fix it?

AB2TC - Knut


Bob McGraw - K4TAX wrote

> While repairing  quite a number of ham radios for others over the years,
> I've made a tidy bit of money repairing radios where hams thought they
> needed "touching up" with regard to alignments.  {If it isn't broke,
> don't try to fix it.}
>
> First, one should use some means and related test and measurement
> equipment to determine "if a radio needs alignment".   In other words,
> if one can't determine if it needs alignment, it probably does not need
> alignment.   Just to jump in an start tweaking coils and trimmers has
> put a lot of money in my pocket.  [In fact, I purchased a new loaded K3S
> with other hams money. :-) ]
>
> Just a word for the wise.......... I have radios which are 20 to 30
> years old which haven't been aligned since ex-factory.  They still meet
> specs and thus do not need alignment today.   Now, if one has replaced
> parts due to a failure, one should determine if any alignment is
> required and if so, proceed.   Just be sure you have correct procedures
> and required and calibrated test equipment.
>
> 73
>
> Bob, K4TAX
> <snip>





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Re: Does the K3(S) need occasional realignment?

Don Wilhelm
In reply to this post by ab2tc
Knut,

Do you have a power loss on some bands that is not cured with a TX Gain
Calibration?
Have you measured the receiver MDS and found it to be lacking from the
last time you measured it?

If the answer to both those questions is "NO", then the answer is that
it does not need any alignment.

Older tube rigs may be a different matter, but modern components are not
as prone to value changes with age as they were "back then".

This applies to any transceiver, and is not particular to the K3 or any
other one transceiver.

I have serviced K1s and K2s K2s that I had fully aligned and calibrated
several years before, and find them still in perfect alignment (although
I do go through the alignment procedures on those I service again just
as a check).

Unless you have adequate instrumentation, I would not attempt it.
It would be simpler to send your K3(S) back to Elecraft than to attempt
it yourself - by the time you obtain adequate instrumentation, you will
spend more money on the project than a trip to Elecraft.

Then you mention the other problem - lack of full instructions.  Those
are not available for the K3(S).  Elecraft has automated testing lines
set up to do that job.

73,
Don W3FPR



On 6/3/2018 4:53 PM, ab2tc wrote:

> Hi,
>
> Very recently there was the same question asked about the K1. I don't recall
> any mention of this topic on the K3 on the reflector. It has internal
> trimmers on the per ham band HF filter. Is it advisable to occasionally
> touch these up? I have no reason to believe that my oldest K3 (ser#82) is
> out of alignment, but I'd like to be ahead of the game. I am old enough to
> have used tube rigs in my early ham career and they definitely needed
> occasional tune up. The narrow band ham band RF filters in the K3 have
> relatively high Q so the slightest component drift will quickly affect the
> shape of the filter curve.
>
> If the answer is affirmative, could we get a procedure for doing it
> properly? Tuning for max signal at the center frequency may not produce the
> proper shape of the bandpass filter (flat top for the required bandwidth). I
> know from my previous career as an RF engineer that tuning LC bandpass
> filters can be tricky.
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Re: Does the K3(S) need occasional realignment?

Bob McGraw - K4TAX
In reply to this post by ab2tc
Knut:

First, let me make it clear,  I do not repair Elecraft radios. In fact
within the past year I've stopped repairing all radios........except
mine.   And in my case, I've sent my K3S back to Elecraft to repair.

Even though I still have some $35K invested in test equipment inventory
in my shop, a dedicated room in my building separate from the house,  I
really don't have the necessary items and tools to work in detail with
surface mount components and the technology, extender boards, test
fixtures and such items as used today.   As to alignments, these are
usually required but only after a component failure and thus it has been
replaced.

So to answer your question; "If you encounter a misaligned K3 in your
repair activities, how do you fix it?"   My answer:  I'd obtain a RA
from Elecraft and sent it to them.   What ever it cost, is what it cost.

Present door to door turn-a-round time to Elecraft for repair is some 10
to 20 days plus transportation.   My K3S was shipped on 5/8/2018 to
Elecraft and is expected to be delivered to me on 6/7/2018 .    That's
awfully close to 30 days.

  73

Bob, K4TAX



On 6/3/2018 4:38 PM, ab2tc wrote:
> Hi Bob and all,
>
> Thanks for your reply. I certainly have no intention to hop in there and
> misalign my radio, so this is why I asked. If you encounter a misaligned K3
> in your repair activities, how do you fix it?
>
> AB2TC - Knut
>


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Re: Does the K3(S) need occasional realignment?

ke9uw
In reply to this post by Don Wilhelm
Interesting topic. I actually had a tx gain cal failure with a new K3S on 6M but a subsequent tx gain try, it passed. I didn’t make any mistakes putting it together. Kind of an anxious moment with a a new rig right out of the box, but it did pass. I’m kind of shy to ever run tx gain cal again. 😳

Chuck Jack
KE9UW

Sent from my iPhone, cjack

> On Jun 3, 2018, at 4:59 PM, Don Wilhelm <[hidden email]> wrote:
>
> Knut,
>
> Do you have a power loss on some bands that is not cured with a TX Gain Calibration?
> Have you measured the receiver MDS and found it to be lacking from the last time you measured it?
>
> If the answer to both those questions is "NO", then the answer is that it does not need any alignment.
>
> Older tube rigs may be a different matter, but modern components are not as prone to value changes with age as they were "back then".
>
> This applies to any transceiver, and is not particular to the K3 or any other one transceiver.
>
> I have serviced K1s and K2s K2s that I had fully aligned and calibrated several years before, and find them still in perfect alignment (although I do go through the alignment procedures on those I service again just as a check).
>
> Unless you have adequate instrumentation, I would not attempt it.
> It would be simpler to send your K3(S) back to Elecraft than to attempt it yourself - by the time you obtain adequate instrumentation, you will spend more money on the project than a trip to Elecraft.
>
> Then you mention the other problem - lack of full instructions.  Those are not available for the K3(S).  Elecraft has automated testing lines set up to do that job.
>
> 73,
> Don W3FPR
>
>
>
>> On 6/3/2018 4:53 PM, ab2tc wrote:
>> Hi,
>> Very recently there was the same question asked about the K1. I don't recall
>> any mention of this topic on the K3 on the reflector. It has internal
>> trimmers on the per ham band HF filter. Is it advisable to occasionally
>> touch these up? I have no reason to believe that my oldest K3 (ser#82) is
>> out of alignment, but I'd like to be ahead of the game. I am old enough to
>> have used tube rigs in my early ham career and they definitely needed
>> occasional tune up. The narrow band ham band RF filters in the K3 have
>> relatively high Q so the slightest component drift will quickly affect the
>> shape of the filter curve.
>> If the answer is affirmative, could we get a procedure for doing it
>> properly? Tuning for max signal at the center frequency may not produce the
>> proper shape of the bandpass filter (flat top for the required bandwidth). I
>> know from my previous career as an RF engineer that tuning LC bandpass
>> filters can be tricky.
> ______________________________________________________________
> 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]
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Chuck, KE9UW