[Drake] TR-7

[Garey Barrell]

Joe -

Good advice.  Often it's not necessary to remove the board completely, 
which particularly in the case of the DR-7 can be problematic.  
Especially the first time or two you do it!  It's usually sufficient to 
just lift the board enough to feel the connectors slide a bit and then 
reseat.

By the way, there is NO RTL logic in the TR-7.  The only RTL I know of 
in Drake Ham gear is in the calibrator for the R-4B.  What you are 
thinking of is ECL, or Emitter Coupled Logic, which was THE high speed 
logic of the TR-7 era.  Power hungry and HOT, but it ran to 250 MHz and 
up.  Getting hard to find these days.  There are only a few pieces in 
the TR / R-7, all on the DR-7 to push that counter to 150 MHz.  The rest 
are all 4xxx series CMOS which is still plentiful.

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B & C-Line Service Supplement CDs
<www.k4oah.com>



Joel Richey wrote:
> I have a late tr-7 (3 piece back panel) and I found over the years that most if not all problems could be solved by removing the boards and cleaning the connectors and reseating em, the TR-7 uses what is called RTL logic andthe DR-7 board runs a little warm, anyways try reseqting all connectors and good luck..
>
> Joe W2DBO
>
>