It turns out it doesn't matter about the bandswitch position - same result
in all positions regardless
of the transmitter freq. The bandswitch seems OK by visual inspection and
with an ohmmeter.
I have to wonder where the power is going. No arcing, no noticeable heating
so far but I
don't run it too long since it is obviously not working correctly.
73, Larry W6NWS
----- Original Message -----
From: "Gary Schafer" <garyschafer@comcast.net>
To: <n8de@thepoint.net>; "'Larry'" <w6nws@arrl.net>; "'Larry'"
<lknain@nc.rr.com>
Cc: "'Amps'" <amps@contesting.com>
Sent: Tuesday, November 16, 2010 10:17 PM
Subject: RE: [Amps] Suggestions - I broke my amp - part 2
> If the output relay was open there would be a large dip in plate current
> when the tune control was tuned with drive applied.
>
> Open bandswitch or switch on the wrong band is most likely. Try another
> band.
>
> 73
> Gary K4FMX
>
>> -----Original Message-----
>> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
>> Behalf Of n8de@thepoint.net
>> Sent: Tuesday, November 16, 2010 7:53 PM
>> To: Larry; Larry
>> Cc: Amps
>> Subject: Re: [Amps] Suggestions - I broke my amp - part 2
>>
>> One thought:
>>
>> Have you checked the output relay to see if it makes contact when fired?
>>
>> If the output of the amp wasn't making it to the antenna, the symptoms
>> you describe would be happening. No RF getting past the relay due to
>> the relay NOT closing properly would give no output to your RF meter,
>> right?
>>
>> 73
>> Don
>> N8DE
>>
>>
>> Quoting Larry <lknain@nc.rr.com>:
>>
>> > A number of you offered suggestions a couple of weeks ago and I checked
>> those
>> > suggestions a couple of times. I have finally got back to trying to
>> > track down what
>> > is probably a silly error on my part that has broken my
>> > Clipperton-L. The mods were
>> > triggered by the destruction of the original parasitic suppressors.
>> > The amp was
>> > working - just not well in all conditions.
>> >
>> > I replaced the power supply board (just an upgrade to better
>> > supply), replaced the
>> > plate RFC to an Ameritron AL-572 RFC along with the parasitic
>> > suppressor board,
>> > changed the plate bypass cap at the power supply side of the plate
>> > RFC to a 0.002uf
>> > value, changed the plate blocking cap to 0.002uf, changed the
>> > filament RFC to a
>> > bigger unit, and changed a couple of doorknobs for 160 (unrelated to
>> > the original
>> > problem of the parasitic suppressors). I haven't gotten to 160 yet.
>> > The current effort
>> > is using 40. The current result is still no output
>> >
>> > 1. There is plate current (as measured by the panel meter) and there
>> > is plate voltage.
>> >
>> > 2. I don't have a HV probe but I could measure at the plate voltage
>> > (at the plate caps)
>> > as the voltage was dropping after turning off the power switch and
>> > it tracked with the
>> > panel meter.
>> >
>> > 3. The idle current seems OK.
>> >
>> > 4. The plate current follows keying. The plate current changes as it
>> > should as the driving
>> > power is increased or decreased.
>> >
>> > 5. Adjusting the output cap controls has no noticeable effect on the
>> > plate current (no dip
>> > etc).
>> >
>> > 6. Using an ohmmeter there is continuity (short) from the output
>> > network side of the plate
>> > blocking cap (on the cap lead) to the output connector. From the
>> > other side of the
>> > plate blocking cap (on the cap lead) to the power supply there is
>> > continuity (short).
>> > Thinking perhaps the new blocking cap might be bad I replaced it
>> > with a pair of 0.001uf
>> > in parallel but still have the same result. (I remeasured the shorts
>> > after replacing the
>> > blocking cap.)
>> >
>> > 7. The output relay is switching as it should. None of the wiring to
>> > the relay was touched
>> > in this mod.
>> >
>> > It has been a long time since I worked on an amp. I am sure I am
>> > overlooking something
>> > small and silly. I was hoping one of the gurus here might have a
>> > pointer or suggestion of
>> > something I might have missed.
>> >
>> > Thanks
>> >
>> > 73, Larry W6NWS
>> > _______________________________________________
>> > Amps mailing list
>> > Amps@contesting.com
>> > http://lists.contesting.com/mailman/listinfo/amps
>> >
>>
>>
>>
>> _______________________________________________
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>
>
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