[R-390] replacement R390A gear clamp source

[Paul Roche]

Thanks so much. I have been reading a ton. It’s fun. 

I have other work to do (replace electrolytics and other paper caps) and will play with it for a while before I screw it up while taking it apart to repair (again).
Sent from my iPhone

> On Jul 25, 2026, at 1:35 PM, Jordan Arndt <Outposter30 at shaw.ca> wrote:
> 
> Paul....
> 
> Seeing that you have a Cosmos PTO, there are 2 seperate adjustments. One sets the end to end 1Mc ten turn coverage, and another that sets the 25kc points which is much more involved and difficult to adjust.
> 
> You should do some reading about the Cosmos adjustments...
> 
> 73...Jordan VE6ZT
> 
> ----- Original Message ----- From: "Paul Roche" <rochep at comcast.net>
> To: "Jordan Arndt" <Outposter30 at shaw.ca>
> Cc: "Barry" <n4buq at knology.net>; "R-390 Mailing List" <r-390 at mailman.qth.net>
> Sent: Saturday, July 25, 2026 9:45 AM
> Subject: Re: [R-390] replacement R390A gear clamp source
> 
> 
> It is a Cosmos 136-1 PTO, SN 21195 (I think that’s means it’s a pretty late one).
> Sent from my iPhone
> 
>> On Jul 25, 2026, at 11:23 AM, Jordan Arndt <Outposter30 at shaw.ca> wrote:
>> 
>> Paul....What you're seeeing is the cover for the adjustment....the real adjustemnt is hidden behind that cover screw which you need to remove. Behind it is a small slotted brass rod that you adjust...I wouldn't try to adjust it until you're sure you have everything properly synchronized.
>> 
>> What type of PTO is it...? Collins type or Cosmos type...?
>> 
>> YMMV....73...Jordan VE6ZT
>