[Drake] R7A service manual

[Garey Barrell]

Dennis -

Thanks for the info.  Just goes to show...  Even a blind squirrel finds 
an acorn once in a while, if ...   :-)

I didn't see how there would be much of a market for a 24V regulator.  
Wonder what they had in mind?

73, Garey - K4OAH
Glen Allen, VA

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



Dennis Monticelli wrote:
> My company manufactured both types and Garey guessed right.  The 24V
> part became obsolete due to low demand and the adjustable 317 series
> was the recommended replacement.  It's performance is a little better
> to boot.
>
> Dennis AE6C
>
> On Thu, Feb 28, 2008 at 2:24 PM, Garey Barrell <k4oah at mindspring.com> wrote:
>   
>> Dan -
>>
>>  My R-7 Service Manual Power Supply Board schematic, dated 12-80, shows
>>  the LM317LZ.  Since R1922 and R1923, which would NOT have been needed
>>  with the 78L24 IC, are the last two resistors on the board it certainly
>>  implies a production change.
>>
>>  The 78L24 was probably NOT an easy part to source, so they just went
>>  with a variable IC and two resistors.
>>
>>  73, Garey - K4OAH
>>  Glen Allen, VA
>>
>>  Drake 2-B, 4-B, C-Line & TR-4/C Service Supplement CDs
>>  <www.k4oah.com>
>>
>>
>>
>>
>>
>>  Dan Cotsirilos K9DTC wrote:
>>  > Does anyone have access to a R7A service manual? I only have a R7 that I can refer to. According to the R7 manual on the multi regulator board the one with the DC to DC is supposed to have a 78L24 regulator. The one that is on my board in that same place is a LM317Z?
>>  >
>>  > What I would like to know is this a 7A update or did someone put the wrong part in. thanks
>>  >
>>  >
>>  > Dan K9DTC
>>  >
>>  >
>>  >
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>>     
>
>
>