- Wavetek 3100 service monitor problems - 3 Updates
- Sony Rcvr STR-DE675 random loud pops - 2 Updates
| captainvideo462009@gmail.com: May 25 04:37PM -0700 I have a Waveteck model 3100 service monitor. I got this unit from a guy about 15 years ago and I think that I used it a couple of times and then put it away for awhile. I recently tried to use it and the keyboard is locked up and the LCD display reads: "A1 Low 0 Drive" I have the complete service manual, and although this error message is mentioned as an important one it does not elaborate on what it might be. It says to call the factory for tech assistance. I'm afraid that ship sailed long ago though. I don't know who might, or even if this unit is still supported anymore. This is admittedly an old unit but a nice one, and I'd really like to get it going. I have some old PRC77 military radios to repair and I could really use this thing. I know that there is a lithium battery inside that could be bad but the book mentions a different code for that fault. Can anyone please help me with this? Thanks, Lenny. |
| N_Cook <diverse@tcp.co.uk>: May 26 08:04AM +0100 > "A1 Low > 0 Drive" > I have the complete service manual, and although this error message is mentioned as an important one it does not elaborate on what it might be. It says to call the factory for tech assistance. I'm afraid that ship sailed long ago though. I don't know who might, or even if this unit is still supported anymore. This is admittedly an old unit but a nice one, and I'd really like to get it going. I have some old PRC77 military radios to repair and I could really use this thing. I know that there is a lithium battery inside that could be bad but the book mentions a different code for that fault. Can anyone please help me with this? Thanks, Lenny. memory backup battery/supercap somewhere? |
| captainvideo462009@gmail.com: May 26 07:10AM -0700 > "A1 Low > 0 Drive" > I have the complete service manual, and although this error message is mentioned as an important one it does not elaborate on what it might be. It says to call the factory for tech assistance. I'm afraid that ship sailed long ago though. I don't know who might, or even if this unit is still supported anymore. This is admittedly an old unit but a nice one, and I'd really like to get it going. I have some old PRC77 military radios to repair and I could really use this thing. I know that there is a lithium battery inside that could be bad but the book mentions a different code for that fault. Can anyone please help me with this? Thanks, Lenny. Well I guess that I should look for this lithium battery. After 30 some odd years I'm thinking that it couldn't possibly still be any good. It's just that it does mention that different error code for a battery though. I doubt that there would be anything like a super cap in this unit. It's too old for that I'm sure. Lenny |
| "G. Paul Ziemba" <paul+usenet@w6yx.stanford.edu>: May 26 12:33AM >determine whether the pops are specific to one channel or the other >One of my favorite debugging tools, for faults like this, is a wooden >chopstick. Oh, very good. I wasn't clever enough to think of that! So far I have determined the pops are in the left main channel but not the right. Still trying to localize the area of greatest mechanical sensitivity - almost anywhere on the board generates a pop, and then it's 30-60 seconds or so until I can reset the "protect" mode by power-cycling. Working on lighter taps! Thanks to everyone else for excellent ideas as well. I'll report back once I get a better idea of the location. -- G. Paul Ziemba FreeBSD unix: 5:36PM up 2 days, 5:06, 7 users, load averages: 0.73, 0.88, 0.85 |
| "G. Paul Ziemba" <paul+usenet@w6yx.stanford.edu>: May 26 05:08AM >> Mark Z. >I will second Mark's comment here. Many a Sony has been "fixed" by resoldering the uPC 2581. I usually remove the solder and resolder. Very common problem. >Dan I used a plastic rod to tap around the board to localize the problem. The two big capacitors were fine, but almost everywhere else wasn't. Connecting only one speaker at a time was a good idea - left main channel only. There were multiple solder joint faults. The big cap in the 30v circuit, c819 (on the PCB layout but not on the schematic), the coil of the headphone relay near it, and the driver ICs (uPC 2581) all had unstable solder (not visible to the naked eye). Working through all of these required multiple disassembly and reassembly iterations (no easy-access panel from below, grr) but now the amp has been running for an hour without a pop. Thanks to all for the various suggestions - all were helpful in reaching a satisfactory conclusion. -- G. Paul Ziemba FreeBSD unix: 10:11PM up 2 days, 9:41, 9 users, load averages: 0.74, 0.71, 0.74 |
| You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com. |
No Response to "Digest for sci.electronics.repair@googlegroups.com - 5 updates in 2 topics"
Post a Comment