Here's some info on the Astron RS-35 as found on the CAP web page: https://ntc.cap.af.mil/
Jack - N7OO ----- Original Message ----- From: Eric Lemmon To: [email protected] Sent: Sunday, June 10, 2007 9:42 AM Subject: RE: [Repeater-Builder] Astron RS-35 Perplexed problem Mark, Try replacing R5, the 1000 ohm voltage adjustment pot. This is a cheap composition-element pot that often gets noisy after the wiper is in the same position for years, in a hot environment. If a poor contact between the wiper and the substrate occurs, the regulator chip thinks the output voltage has dropped and it will cause a spike. You can verify whether the pot is bad by first noting its current position, then sweep it back and forth several times to "polish" the wiper, and leave it at a slightly different position than before. If the output voltage is now stable (it will be higher or lower than before, of course), you've found the problem. You might think about remotely mounting a high-quality wirewound pot on the front panel, where it's convenient to adjust and away from the hot environment. If the pot doesn't solve the problem, call Astron at 949-458-7277 and ask for Fred in Tech Support. 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Mark Boden Sent: Sunday, June 10, 2007 9:06 AM To: [email protected] Subject: [Repeater-Builder] Astron RS-35 Perplexed problem I am struggling on an old RS-35 that is spiking. Currently I have the crowbar disconnected for trouble shooting. The power supply will come on with no load connected. After a couple of minutes or seconds as the case may be, the output will start to show spikes. Using my Fluke 87 to record, it will have a quick spike up 1 volt to 2 volts. More than enough to set off the crowbar scr if hooked up. Even with small to moderate loads of up to 4 amps it will do the same. Have changed the LM-723. Reflowed the entire circuit board. The supply to the 723 looks clean. But after a month on the bench, I still am no smarter about what is wrong. I have swapped parts between this and one of the spare RS-35 but no luck. Any ideas? Mark - N4TZV Messages in this topic (0) Reply (via web post) | Start a new topic Messages | Files | Photos | Links | Members Change settings via the Web (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest | Switch format to Traditional Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe Recent Activity a.. 22New Members Visit Your Group Y! GeoCities Create a Blog And tell the world what you think. Drive Traffic Sponsored Search can help increase your site traffic. Yahoo! Groups Start a group in 3 easy steps. Connect with others. . _._,___
