Norm, I've been to your site many times over the last several years. I've had a few R390As and now have just my one R390. Yours is just beautiful. I've cleaned mine, along with the gear train, as well as repainting the front panel, knobs, etc., and it looks pretty nice. Mine wasn't in as good of a shape as yours and I don't think it ever will be but it's good enough.
Thanks again for the great pictures! 73, Barry - N4BUQ On Sat, Feb 14, 2026 at 2:31 PM Norman Drechsel <[email protected]> wrote: > Hello to all on the group. I've been a long time member and don't recall > having ever posted, but couldn't help but chime in on R390 gear cleaning. > I have restored about two dozen R389, R390, R390A and R392 receivers over > the years (and still have one dozen). Gear cleaning was always a challenge > and (unless something was broken) couldn't bring myself to taking all those > split gears and shafts apart and then putting it back together. It's a > formidable task and I salute all who have been brave enough to meet the > challenge. > > Here are links to photos of an R390 RF deck I restored about ten years ago: > > http://www.wa3key.com/r390/r390-11.jpg > http://www.wa3key.com/r390/r390-12.jpg > http://www.wa3key.com/r390/r390-13.jpg > http://www.wa3key.com/r390/r390-13.jpg > http://www.wa3key.com/r390/r390-15.jpg > http://www.wa3key.com/r390/r390-16.jpg > > Here's how I do it. The obvious first task is to drop the front panel and > pull the RF deck. After tying the connectors back and removing the Veeder > Root counter, I attach four Nylon plates to the front panel like feet so it > can be stood face down in a large ultrasonic cleaner. I fill the tank with > a mixture of water and Simple Green so the level covers all the gears but > keeps the chassis and electrical components dry. I then use an emersion > heater to warm the cleaning solution and run the ultrasonic for about 15 > minutes. If all the gunk didn't come off I run for another 10-15 minutes. > > Then the tank is drained refilled to the same level with WD-40 (yes that's > a lot of WD-40, but it stays clean and is reusable) and run the ultrasonic > for another 10-15 minutes. This step displaces every trace of water, even > from between the split gears and shaft sleeves. > > Following the WD-40 cycle I reclaim the WD-40 (the water stays at the > bottom so is easy to separate) and then spray the gear assembly (outdoors) > thoroughly with compressed air which only leaves a film behind. A thin > application of synthetic motor oil with a brush is the only lubrication I > use. > > This process works great for the R390, R390A and R-392, but the R389 is a > whole different "animal" and can only be done the hard way. > > If you'd like to see the rest of the R390 photos, replace the digits > following the "-" in the URL with "01" thru "42." Or if you want to view > the photos from all 3 restorations, go to > > http://www.wa3key.com/r390/ > http://www.wa3key.com/r390a/ > http://www.wa3key.com/r389/ > > and you'll find a list where you can click on one photo URL at a time and > use your browser's back button to return to the list. I decided to take > document these restorations because all three were original and unmodified. > > 73 de Norm - WA3KEY > [email protected] > ______________________________________________________________ > R-390 mailing list > Home: http://mailman.qth.net/mailman/listinfo/r-390 > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ R-390 mailing list Home: http://mailman.qth.net/mailman/listinfo/r-390 Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
