[Premium-Rx] Any R7 Mechanics Out there?

[lrlayton at cox.net]

Hello Scott,

 I just checked the VCO self test on my Drake R7 and it settles down at 17356 and 32989 kHz after a few seconds, so yours doesn't seem too far off. The alignment requires a jumper board with several components on it. There is a seller on ebay that has a kit with this board and other extenders for the R7 and TR7. I don't know where else to get one unless you can find one to borrow somewhere. I'ts worth taking a look at ebay to get an idea what the jumper board looks like. 

In the past I had an intermittent problem where the lower 2 bands were both 500 kHz off and the highest band would not lock in. That was caused by a bad solder joint on the DR7 board on the set of pins at the back left side of the board, so that might be something to look at.

Les


---- Ka9p--- via Premium-Rx <premium-rx at mailman.qth.net> wrote: 
> I'm looking for a good R7 mechanic or advice re same.
>  
> My R7 wants to start up at 23 mhz when switched to 21 mhz, and the three  
> low frequency bands, LF and AM broadcast, also want to start a few mhz  
> higher than they should.
>  
> I've reseated and deoxited all the pins on the boards.
>  
> The service manual describes a self test where you throw the  FIXED switch 
> to let the VCO free run and settle out, in one case at about  17 mhz, and in 
> the other at about 32 mhz if the VCO is properly adjusted.
>  
> When I do this test, the VCO settles out at 18 and 34 mhz  
> respectively....although I'm not sure if 17 is about 18 or if 32 is about 34 for  the 
> purposes of the self test - no further info in the manual re that, other  than the 
> alignment instructions if it's not.
>  
> To do the alignment the DR7 board has to be removed, and a header installed 
>  to allow access to the board with the required VCO adjustment slugs.
>  
> So if anyone has any idea about any of the following issues, I'd be in your 
>  debt for your thoughts.
>  
> 1) whether 17+18 and 32=334 mhz for the self test
>  
> 2) where on might beg, steal borrow or find parts to make up the required  
> header for alignment of the VCO
>  
> 3) where there's a great R7 mechanic that does this, still; and
>  
> 4) if that fault looks familiar and it might be something else, what it  
> might be.
>  
> I realize this is a bit below Premium grade, but know the knowledge on here 
>  is deep, so thought I'd give it a shot.
>  
> Thanks, alot, 
>  
> Scott  ka9p
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