[AMRadio] RETRO 75 Build

LEE BAHR pulsarxp at embarqmail.com
Wed Mar 24 00:45:23 EDT 2010

I got the PC board populated with all the parts this evening but as yet have 
not tested it out.  Everything went together as planned and I did not put 
any parts in the wrong holes by mistake.

1.  You need to cut wire for the toroids a little shorter then suggested, or 
you will run out of wire before the last toroid is wound.  The kit supplies 
enough wire to do the job, but the suggested starting length is lavish 
compaired to the amount of wire supplied.
taking that into account,  I did have enough wire in the kit to wind all the 

2.  I did use non supplied Thermal grease on both T-220 heat sinks.

3.  I did fashion some HC-49 crystal sockets for the two transmit crystal 

I started with an 8 pin gold plated machine IC socket.  I first cut two 
strips of 4 pins and then cut each segment down to 3 pins each.  I then cut 
the center pin bottom out.  The remaining 3 pin segments fit perfectly into 
the RETRO 75 board.  I'll plug the top center hole of each strip as it won't 
be used.  To cut the socket up I used a diagonal cutter.  It cut like butter 
as the plastic is very soft.  I did all the trimming and cutting with the 
diagonal cutter.  It took less then a minute to fashion both crystal 
sockets.  The 3885 khz HC-49 crystal fits very snuggly into one of these 
sockets.  This socket business really came out nice.  I'm glad I did it.

4.  My Cobra HG-M73 CB Dynamic mic I purchased for $11.00 new on E-bay is in 
transit.  (Seller has many to sell plus many others do too).  It is fitted 
with a 4-pin mic plug.

5.  My TenTec TP-41 case for $6.71 is also on it's way.

The parts are spaced at a reasonable distance but the board is still small 
(5 1/4 x 3 1/2 inches).  The parts are not packed as densly as on the Ft 
Tuthill 80.

Lee, w0vt 

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