Adventures in Amateur Radio

Scappoose, Oregon, USA    -     Columbia County

ITU Zone 6         CQ Zone 3         Grid  CN85nt



.: Drake R4C Restoration


  My Drake R4C Restoration

In February of 2010 I answered a Portland area Craig's List ad for "HAM RADIO GEAR, $600 OBO. In the ad was a very fuzzy picture of a stack of Drake equipment. I have always wanted to have a C line to create my vintage "boat anchor" station, and this was my chance. I was the first responder to the ad, which it turns out was a PAIR of Drake C lines (R4-C, TX4-C, MS-4 with PS-4 installed), a Kenwood TS-830S, a Kenwood AT-230 antenna tuner, a Heathkit GR-64 General Coverage Receiver, and box of "stuff", most of which ended up in the garbage. The radios had come from the estate of a ham in in Olympia, Washington, and had been sitting in the daughter's Portland area garage until she had the courage to part with some of her father's belongings. Everything was dirty and dusty with slight tinges of rust, but it was all there.

The Resurrection of a R-4C

Which to start with? Both R-4Cs were in the later and more desirable serial number range, 21xxx (1973 vintage) and 26xxx (1976 vintage). The 26xxx radio was newer but very dirty and bone stock, with a bit of minor rust spots on the chassis, while the 21xxx unit was cleaner (no rust) and (Surprise!) had all the factory goodies installed!. This included ALL of the accessory filters (including the 6 KHz AM filter), NB-4 noise blanker, and a whole bunch of extra band crystals. On the down side, the older unit looked like it was well used and worn, both inside and out. I slowly fired up the receivers using a variac to re-vitalize the electrolytic caps and found out that both radios "kind of" worked. Cleaning the switch contacts made a world of difference, but the later unit came to life and was receiving signals first. I decided to restore that radio as it was the later serial number, and appeared to have had much less wear and tear on it over the years. The other would donate its accessory goodies for the common good.

Time to clean things up a bit! I started by completely dismantling the R-4C's faceplate, removed the tubes and band crystals, then removed the PTO assembly to keep water out of it. This was followed by a trip though the dishwasher (set to delicate, of course!).  Here is a picture of the washed chassis, sans tubes, PTO, filters, crystals, and noise blanker. What a difference a few minutes made!:

After a week of dry time, I sanded the rusty parts of the chassis with 600 grit sandpaper (mostly along the bottom edges), then sprayed the affected areas with clear Krylon paint. After that dried, I re-installed the PTO (after a cleaning of the gears and some teflon lube), checked and reinstalled the tubes and band crystals, then proceeded to rob the other R4-C of its AM filter, three accessory filters (1.5 KHz SSB, 500 and 250 Hz CW), and the Noise Blanker. Believe it or not, it all worked when it was put together, (except for a nasty bacon frying noise from the 3rd mixer...). OK, there is a fix for that!

Time to get on the phone with Rob Sherwood of Sherwood Engineering to get all the mods that make the R-4C sing like a modern radio! About $130 later I had the new audio amp board (AMP-4), new product detector (PD-4), new power supply board (PS-4) and the new solid state 3rd mixer board (MIX-4), which replaced the 6EJ7 3rd mixer tube and eliminated the bacon frying pan noise the radio had. All were very easy to install on a rainy Sunday afternoon, thanks to the great detailed color instructions provided by Sherwood in the kits. I also replaced the dial lamps with blue LED versions, purchased from a supplier on E-Bay.

Were the mods worth it? YOU BET. They made a world of difference in how the radio performed! I would rate the modified R-4C's sensitivity at least as good as my modern Yaesu FT-2000, maybe with an even quieter background noise level. I have not gone to the point of installing the extra Inrad GUF-1 filtering to this radio since it is not going to be used for anything serious, just occasional nostalgia QSOs. Here is a picture of the "leftover parts" after the Sherwood boards were installed:


Next job, repair the matching TX4C, which has a PTO that is off frequency.....






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