[TenTec] Scout 555 - no output

Malcolm McLeman f5vbu at cegetel.net
Sun Dec 9 02:47:46 EST 2018


A man after my own heart and exactly how I got my Omni VI back on the 
rails with only a multimeter and a hi-z crystal earpiece for RF sniffing. 73

On 12/9/2018 5:23 AM, Carlos wrote:
> Hi Mike,
> 
> What I'm going to propose you is going to sound a bit crude, but it might
> help.
> 
> If you have a receiver you can tune it to the frequency where the 555 is
> operating and instead of using an RF probe, you can touch the
> base/collectors of the transistors you want to test with your finger (naked
> finger or helped with a small piece of naked wire or a paper clip
> unfolded).
> 
> If there is RF at the points you are probing, the receiver will show it
> instantly. It might help if your RX antenna consist in a short (3ft) wire
> close to the 555 under test rather than a large antenna far from your shack.
> 
> With this technique you can check the presence of the heterodine xtal
> oscillators or even the PTO.
> 
> Does it make sense?
> 
> 73,
> Carlos VK1EA
> 
> 
> 
> 
> On Sunday, December 9, 2018, Mike Fishman NK8S <nk8sradio at gmail.com> wrote:
>> Thanks very much for the replies and tips Gary and Steve!
>>
>> Steve, I don't recall when precisely it failed - I'm guessing I turned it
> on and found it as is. I was using CW and the internal keyer
> previously...will try and locate the reverse polarity diode to eliminate
> that as the issue. Thanks again!
>>
>> Gary, I'm thinking I'll grab a kit version of an rf probe for the
> multimeter and give that a try - thanks very much!
>>
>> Very 73, Mike NK8S
>>
>> _______________________________________________
>> TenTec mailing list
>> TenTec at contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>>
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
> 


More information about the TenTec mailing list