[R-390] SP 600 Upgrade Progress

[Perry Sandeen]

Yo Dudes,

 My RH is healing up nicely and I expect to beback to full use in a week or so.  Themain problem is when I stretch my hands there is some scar tissue resistancebut the surgery was well worthwhile.

 Thanks to those who sent encouraging comments.

 Also thanks to Dave Wise for providing theBFO injection value I needed.

 I’ve been working with Bob Thomas VE3TOU ofTreetop Circuits who has developed and sells SSB adaptor boards for the CollinsR390X and R388 receivers to produce a SSB board for the SP 600 receivers. He isa retired EE who does this as a sideline.

 While there have been many SSB conversionsfor the 600 in the past, this is different as being a standalone unit thatdoesn’t require changing the existing circuity. Instead, all the required circuitry is all on one board.  There are IIRC six wires that are attached tocircuit point and one or two components are removed.  The circuit is activated by turning on theBFO.  Power comes from the 6.3 voltfilament supply. 

 This 600 SSB PCB board saga has continued ata blistering snail’s pace.

 Bob has adapted his current PCB to the SP 600with only having the schematic and me sending him the physical location informationwith lots of email correspondence.

 Four prototypes have been produced and I hopeto get one installed in the next few weeks as it's coming from Canada.

 It is mounted internally in the space nowused by the C129A/B.  Replacement capacitorswill be provided.

 Ordered repro replacement dials from RadioDaze are long, long overdue.  When theyarrive I’ll pass on the details to the list.

 I have H-101H digital readouts from ESP in FLto place in the RH bezel in front of the logging scale. They will fit nicelybut I haven’t quite figured out how to mount them. Although they don’t workabove 50 MHz they will work well for my intended application.

 For chassis polishing I first used Bon Amicleansing powder made into a thin slurry.

 I used a $30 orbiting polisher from Lowe’s. Works well but makes a big mess.  Throws slurry all over the place.  Inside a large cardboard box would have beenmuch better idea.

 The final polish was Mothers Mag and Aluminumpolish. $10 a can at the auto store.

 The downside (there always is one) is thatthe polish contains some sort of wax.  Thishas to be removed with cotton balls (no scratching) and Acetone that has to beused OUTSIDE and in fresh air. It evaporates quickly and is very flammable.Also avoid breathing the fumes.

 The results I achieved was taking a “fromGandpa’s garage” oxidation to a mirror finish that I desired.

 Never-Dull will also work very well. It’s bigdisadvantage is cost. From polishing other panels I estimate that it would take$60 to $70 to do what cost me about $10 of Mothers. Another disadvantage isthat Never Dull leaves a faint kerosene smelling type of odor.

 More later as things progress.

 Regards,

 Perrier