[AMRadio] GK500 OTA almost


Collin n4tua at aol.com
Thu Jan 5 21:30:11 EST 2017


Great Day, we got it. I believe the GK500B is behaving now. It was parasitic oscillations and Rob hit it right on. I should have tried that first. Took two 240 ohm two watt carbon resistors from the junk box. Didn't have any 200 ohm. Paralleled them and wound 4 turns of wire around and replaced that copper strap with my new lash up. Now she tunes very smooth and predictable with NO arc/flash and no wild uncontrollable plate current. There may well be other GK500s out there that would benefit from this simple and cheap modification. 

You guys on here are great and I thank each of you for the inspiration and help. This is a great community of AMers. 

Your right Rob, I feel like a 5 year old at Christmas. 

Now, to get that modulator deck put back together. Stay tuned. 

Good Day, Collin

On Jan 5, 2017, at 6:31 AM, Rob Atkinson <ranchorobbo at gmail.com> wrote:

>> 
>> WRL documentation is sometimes terrible Collin.
> 
> One of the first things I had to discover is that manufacturer
> schematics are often not telling me what I should see for the item in
> front of me.
> 
> A lot of them made little changes in mid-production without changing
> the schematics or parts lists.   If you run out of 200 ohm resistors
> and have to keep the assembly line going you raid the 400 ohms and
> parallel two and keep moving but a manual re-print for that?  Too
> costly.
> 
> In the old days computer inventorying and next day shipping didn't exist.
> 
> Rob
> K5UJ
> 



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