[Elecraft] K1 Issue. Lost reception when transmitter stage completed.

[Don Wilhelm]

Les,

50 uV is not a large enough signal to see on a 'scope or RF probe. You 
really need 1.4 volts (or whatever is specified in the procedure) of RF 
input.

I suggest you build the simple oscillator shown in the Signal Tracing 
appendix of the manual.  It has good output for that purpose.  The 
crystal should be at a frequency within your tuning range.

73,
Don W3FPR

On 8/22/2014 3:07 PM, Les Garwood wrote:
> Thanks again,  Don.
> I've been using Elecraft's signal injector;  you may know it puts out 50
> micro volts on the high setting.
> I'll try your suggestions but I think I did part of them already.
> BTW, I'm using my Android phone so it's tough to write a lot of detail.
>
> Les
> On Aug 22, 2014 11:05 AM, "Don Wilhelm" <w3fpr at embarqmail.com> wrote:
>
>> Les,
>>
>> You did not mention your test gear nor any information about your setup,
>> so I have to make some guesses and ask some groundwork questions.
>>
>> Are you injecting RF from a signal generator to the BNC jack?  If so, is
>> that signal large enough to register on what you are using to determine
>> signal or no signal ('scope with 10X probe or RF Probe)?
>> Do you have the jumper installed in J2 of the band board?
>>
>> Turn the signal generator off, then on while observing the level at band
>> board J8 pin 8 - you should see a rise in the RF being measured.  If not,
>> the signal level is too low to register on your measurement device.
>>
>> The Signal Tracing section starting on page 5 of the K1 manual appendix
>> gives you an orderly sequence for troubleshooting.  Where does the signal
>> level drop below the expected level?  That point is just past the point of
>> failure.
>>
>> 73,
>> Don W3FPR
>>
>> On 8/22/2014 1:03 PM, Les Garwood wrote:
>>
>>> Dear Fellows,
>>>
>>> I just finished construction of my K1.  The receiver stage worked
>>> perfectly
>>> until I finished the transmitter stage.  I still get audio hiss and volume
>>> but no signal on any band, AGC on or off, attenuator on or off.
>>> All the voltages and resistances check out except the anode of D9,
>>> according to the manual, is supposed to be > 100k.  I'm sure this is an
>>> error, however,  since the DC path to ground from that point goes through
>>> three resistors and a choke totalling only about a couple K,  which is
>>> what
>>> I measure.
>>> I still get rf out of the VFO, and can trace it through the filter board,
>>> J6, at pins 1,2 and 6, with my scope.  However,  there is no trace of
>>> signal rf from the antenna on pins 1 or 8 of J7.
>>>
>>> I have no rf at the attenuator relay either, at pin 3, or any other.
>>>
>>> I can't quite figure out yet how the TR switch circuit works (or doesn't
>>> perhaps) so it's hard to troubleshoot if it is the problem or not.
>>>
>>> Needing the filter board in place makes trouble shooting all the harder
>>> too.  I wish I had a layout view showing the bottom of the rf board to
>>> help.
>>>
>>> As always, any comments welcome and appreciated.
>>>
>>>
>>>
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