Sansui 8080 fuse locations?

Discussion in 'Exclusively Sansui' started by 11B40, Jul 14, 2017.

  1. 11B40

    11B40 New Member

    Messages:
    4
    I bought the 8080 new around 1976. I was changing the front end dial lights and must have grounded somewhere. All the lights are now out. I've found the main power board and checked all of those fuses. I understand that there are more fuses for the lights somewhere. I cannot see them with top and bottom off the receiver. Any ideas?
    thanks
    Dave
     
  2. DougBrewster

    DougBrewster AK Subscriber Subscriber

    Messages:
    405
    far as I can figure it's F05 or F06 on the power supply board F2546; one of them is for the FM stereo lamp and the other for the general lighting but I can't tell which is which..
     
  3. Hyperion

    Hyperion Roobarb & Custard Subscriber

    Messages:
    40,178
    Location:
    Hertfordshire, UK
    There is an 18 ohm fuse resistor on the F-1470 PCB, that seems to feed the dial lights, could this be open?
     
  4. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    Are the lights for the tune and signal strength meters lit? If so the problem is likely to be the function switch. If they are not lit either, and you have checked the fuses on the power supply board with a voltmeter, then it's probably the fuse resistor mentioned by John.

    - Pete
     
    Hyperion likes this.
  5. 11B40

    11B40 New Member

    Messages:
    4
    The power meter lights were both off, one function bulb (FM) was out, all the rest were ok. I was putting the plastic fixture (with 4 fuse type lights) back into position after checking those bulbs and like an idiot I didn't kill the power. Apparently something touched the flat board adjacent to it and all the lights went dark.I checked all the fuses with an olm meter, all show good. What is a fuse resister? and what does it look like on a schematic?
    You guys are fabulous!
     
  6. 11B40

    11B40 New Member

    Messages:
    4
    I took a closer look at the main fuses. I worked for the phone co for 40 years and am used to using a KS meter for checking olms. The radio shack multi meter I have shows gobledygook instead of shorts etc. Anyway, the 1A fuse was in fact blown and when I replaced it, the lights returned. The power meter lights are still out and I'd bet money that the fuse/resistor on 1470 is in fact blown. I'm going to bridge past that part and see if the lights return. If so i can replace that part or jump past it? Having a bit of trouble getting the 18olm fuse/ res.
    Thanks
    Dave
     
  7. Hyperion

    Hyperion Roobarb & Custard Subscriber

    Messages:
    40,178
    Location:
    Hertfordshire, UK
    Don't 'jump' it! (i.e. 'short it') - it's there for a reason, and don't bother with a fusible resistor replacement - just get a metal film resistor of the same wattage (and resistance).
     
  8. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    The power meter bulbs are prone to fail. They are probably just burned out. The power meters have fuse resistors on the board attached to these meters. The resistors in the bulb circuits are there to drop the voltage to the bulbs thereby increasing the life of the bulb. It's unlike any of the fuse resistors have failed.

    The best way to check these fuses is "in circuit" with a voltmeter. You should have voltage on both sides of the fuse. If it only shows voltage on one side, the fuse is blown. Just be sure to set the meter correctly, the lamp fuse is AC voltage and I believe some of the other are also. It's not uncommon for the fuse clips to spread and not hold the fuse tightly.

    - Pete
     
  9. 11B40

    11B40 New Member

    Messages:
    4
    Hi Pete. I checked the only rest/fuse on 1470 that I could see from the back. It was fine. I've ordered a new set of bulbs that are apparently genuine or close matches. They come with the little rubber grommets that seal off the bulbs. I'll change them when they arrive. I've used a lot of Deoxit on switches and they sure look clean. This machine has a checkered past. I bought a new 8080 along with a couple of new AR 12s, about $1100 worth of gear in 1976? Sometime in 1993 I took it into a repair guy in Rohnert Park to get some bulbs changed. I make the mistake of telling the guy that at that time these machines were valuable to Japanese collectors. He said that he had a couple in the back. Well, when I picked it up, it wasn't my machine. Every thing was pristine on mine, the one the guy gave me was just not right. I pointed this out, but by that time he wasn't budging and my only course was to call the cops and I hadn't marked mine to prove my point. So this one is what I got. It is nice but nowhere near what my original 8080 was. I had babied that piece of gear. I have babied those AR 12s as well. In 1985 I replaced both bass speakers and new foam fronts from AR. The foam went away on the drivers and I refoamed the drivers and mids a few years ago. They still sound good.
    Thanks for your help
    You have no idea how helpful you have been.
    D
     
  10. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    The power meter lamps are tricky to replace. It takes a good deal of disassembly to get to them.

    - Pete
     
  11. Skywatcher

    Skywatcher AK Subscriber Subscriber

    Messages:
    39
    The meter lamps are just a 6.3v grain of wheat bulb. And I use nipples for tattoo machines for the grommets. I have the red silicone ones and they fit perfectly in the meters, They are 5mm OD, and 3mm ID. I just recently changed them out in both my 9090db, and changed the ones out in my QRX-7001 2CH/4CH display.
     
  12. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    I did a quick search looking for those silicone grommets. Now the banner ad at the top of this page is pitching tattoo supplies including rubber nipples. I suppose the ad could be triggered by a word search of this thread too. None of the ones I see online say they are silicone. They are just listed as "rubber." Cheap rubber may not be able to hack the heat of the bulb but silicone will with no problem.

    - Pete
     
    Skywatcher likes this.
  13. Skywatcher

    Skywatcher AK Subscriber Subscriber

    Messages:
    39
    http://www.ebay.com/itm/100X-Silico...var=551589558686&_trksid=p2057872.m2749.l2649
     
  14. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    Thanks. I can't believe how cheap they are. Under $2 for 100, including shipping from China!

    - Pete
     
  15. Skywatcher

    Skywatcher AK Subscriber Subscriber

    Messages:
    39
    How about it! And to think they are still making a profit. The 6v grain of wheat bulbs were $12.99 for 100. But some things do take a while to arrive. 2 weeks in this case. Kinda like the old saying "taking the slow boat to China". lol!
     
  16. LBPete

    LBPete Rolling Along Subscriber

    Messages:
    10,932
    Location:
    Long Beach, CA
    For $2 you can't complain about the wait. I haven't done one in awhile. It's such a pita to get to them, I usually put in LEDs so I never have to do it again.

    - Pete
     
  17. Skywatcher

    Skywatcher AK Subscriber Subscriber

    Messages:
    39
    What is nice is these grommets will also be suitable for 3mm LEDs. And the rubber ones won't suffer from the heat using LEDs too. But from my experience with "Chinese" rubber, it doesn't last very long no matter what. It's not very "ozone" resistant and cracks within a year sometimes. Silicone by it's very nature is much more resilient.
     

Share This Page