[R-390] R-390 non A 12khz jump

[Bob Camp]

Hi

Even a “tap with a pencil” sort of test might well identify the part that’s the problem. I used to have 
a plexiglass rod in my tool kit for that sort of stuff. Way safer than “tap with your finger” on tube gear. :)

Bob

> On Dec 27, 2024, at 3:14 PM, Kevin Schuchmann via R-390 <r-390 at mailman.qth.net> wrote:
> 
> 
> Thanks to Tisha and Jacques,
> 
>   It is a model 1 PTO and I have started the disassembly  and will check those capacitors closely.
> 
> Kevin
> 
> 
> 
> On Friday, December 27th, 2024 at 10:32 AM, Tisha Hayes <tisha.hayes at gmail.com> wrote:
> 
>> 
>> 
>> I would suspect a capacitor in the PTO circuitry that is on the verge of
>> failing.
>> 
>> A can of freeze spray may help you isolate the specific component; Maybe
>> even tapping on caps/resistors with the tip of an insulated tool might help
>> identify if there is a cracked component that works differently.
>> 
>> The ballast tube would not be so 'precise' in causing a 12 KHz offset. It
>> is also a very simple thermonic device with an iron filament in a hydrogen
>> atmosphere that is just a current regulator.
>> 
>> Ms. Tisha Hayes, AA4HA
>> 
>> "We live in accordance with the flow of the times"
>> -Yoshio Mizuno
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