[Drake] Re. Going Price of R-4C

[Don Allen]

I purchased a R-4B in the early '70s and a R-4C in 1978.  I still have 
both, and use them daily.  The R-4B is still in perfect condition, 
electrically and aesthetically - and is totally "stock."  The R-4C SN 
27K+, is not stock.  I have applied very selective Howard Sartori and 
Rob Sherwood mods to the rig, and all have been done professionally with 
total documentation should someone in the future choose to reverse the mods.

Most, if not all, the mods to the R-4C were for CW use.   With the 
600Hz  6-pole 1st I.F. filter, switchable 500Hz, 250Hz, and 125Hz 8-pole 
xtal lattice filters in the 2nd I.F., the R-4C is truly a remarkable 
receiver for CW use.  Properly aligned, I've checked the MDS at -142dBm 
and the ulitmate rejection of the cascaded filters at over 110dB.  
Overall dynamic range is fine for my operations.

Other than the filter additions, the only electrical mods applied were:  
low-voltage power supply, product detector, and audio amp (but, not the 
LM383T; rather an LM380).  All mods were implemented with glass-epoxy 
PCBs, so that by desoldering a few wires, the rig could quickly be 
returned to stock.

If you've always used a R-4C with the stock 8kHz 4-pole 1st I.F. filter, 
and have never used one with the switch or relay-selected 600Hz 1st 
I.F., you don't know what your missing.   And, the very rare Fox-Tango 
GUF-? CW filter mod which included two mini-relays on the same PCB was 
also an excellent performer.  Perhaps not the ultimate rejection of the 
Sherwood filter because of its location, but still a fantastic performer.

Properly selected electrical mods, done very sparingly and 
professionally, with the xtal lattice filter filter additions make the 
R-4C one of the great CW receivers of all time.

Don W9CW
Urbana, IL