SX 1080 tuner reception weak

Discussion in 'Pioneer Audio' started by DUALityOFman, Jan 9, 2018.

  1. DUALityOFman

    DUALityOFman Active Member

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    176
    I have an SX 850 and a 1080, which I have had just a few weeks. They both work well and sound great, but the reception with the 850 is MUCH better than the 1080 in the same location with the same antenna. They are in a basement, so I would attribute the difference to that if the 850 wasn't bringing in stations well. What should I try first...then second...third?
     

     

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  2. john stumpf

    john stumpf AK Subscriber Subscriber

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    there could be something else im sure,but my money is on an alignment.
     
  3. dr*audio

    dr*audio Fish fingers and custard!

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    Most likely it needs alignment.
     
  4. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    x3 for alignment.
     
  5. DUALityOFman

    DUALityOFman Active Member

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    Does this involve adjusting caster and camber? I'm not seeing any unusual wear on my tires.
     
  6. DUALityOFman

    DUALityOFman Active Member

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    Seriously, can someone direct me to a good set of alignment tools for cheap?
     

     

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  7. rcs16

    rcs16 Super Member

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    Digikey has a kit, I am not sure if it contains the correct tool sizes. Know one has said that it does not.
    https://www.digikey.ca/product-detail/en/aven-tools/13016/243-1016-ND/600970.
    when you associate cheap tools and aligning FM tuner, I cringe because the two do not usually go hand in hand, you usually need good test equipment in order to properly measure and align a FM tuner.
     
  8. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    No not the tyres, just turn your receiver over and make sure all four feet are pointing in the same direction :p. No seriously l use a plastic tool kit much like this one https://www.amazon.com/Philmore-Ant...rd_wg=729T9&psc=1&refRID=1NA98B0Z2EWSYY5THZ10

    As the other guys said, it is prob the alignment. You could always start by tweaking the front end using an FM station up the higher end of the dial.
     
    Last edited: Jan 10, 2018
  9. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    Actually that tool kit is no good as it doesn't include the hex that you will predominantly use.
     
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  10. dr*audio

    dr*audio Fish fingers and custard!

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    No, you can't do this yourself! You can screw it up worse than it is. This is a job for an competent tech with rf experience and specialized equipment. If you tell us your location we may be able to refer you to someone.
     
  11. dr*audio

    dr*audio Fish fingers and custard!

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    ACHTUNG!!!

    Das machine is nicht fur gefingerpoken und mittengrabben. Ist easy schnappen
    der springenwerk, blowenfusen und corkenpoppen mit spitzensparken. Ist nicht
    fur gewerken by das dummkopfen. Das rubbernecken sightseeren keepen hands
    in das pockets. Relaxen und vatch das blinkenlights!!!
     
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  12. DUALityOFman

    DUALityOFman Active Member

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    Um. Was ist los?

    Someone was kind enough include instructions for doing a quick alignment, so I thought I'd give that a try. I'm not totally incompetent, as I've refurbed a couple dozen 40s and 50s jukeboxes, pinballs, coin ops....watches...and do my own automotive. With his guidance, I think I can give it a try. I just wanted to know which sizes and types of tools l will need.
     
  13. DUALityOFman

    DUALityOFman Active Member

    Messages:
    176
    You know, it's important for one to know his limitations, but I have found that many fear jumping in and trying to fix things. I remember the first time I changed drum brake shoes on a 65 Mustang...all those springs and brake dust....and I was 16 ish. I got it apart and couldn't get it back together, so I scratched my head, removed the other rear tire, and used the assembled brakes to put the one I was working on back together. That process has been repeated hundreds of times over the years. Sometimes I had to give up and let a pro intervene, but more often, I did the work myself, and it was very gratifying (and saved much money). From sweat fitting copper plumbing to replacing the mainspring and balance staff in an old watch, I like taking the chances. If I do more damage, I'll deal with that.
     
  14. dr*audio

    dr*audio Fish fingers and custard!

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    Location:
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    Since you are good with your hands and set on doing this yourself I'll give you the following pointers:
    Service manual is available free here: http://www.kallhovde.com/pioneer/sx-1080sm.pdf
    1. Do not mess with the discrimintator adjustments. These are the 2 adjustments in the T6 transformer. You need special test equipment to adjust them and you CAN'T do it without this equipment, and you WILL end up wth distorted audio and probably no stereo FM.
    2. You CAN carefully adjust the front end for best signal strength. Connect a proper FM dipole antenna. Tune to a known good station on the lower end of the dial, the exact frequency doesn't matter, anything in the 80's or low 90's.
    3. Adjust T1, T2 and T3 for the highest signal on the signal strength meter. Use a plastic tool, NOT metal, you can break the ferrite cores.
    4. Tune to a known good station on the upper end of the dial.
    5. Adjust TC1, TC2 and TC3 for highest signal on the signal meter. Remember what number you got.
    6. Go back and forth between the low end and high end and keep adjusting until there is no improvement on both ends.
    7. Adjust T5 for highest signal level on any station you want, doesn't matter which end of the dial.
    8. If this doesn't improve the reception there is a bad component and a trained tech with rf equipment is going to have to trace the rf signal and see where it is being lost.
    Tools:
    Aven makes a good alignment tool set. Part# 13.016. these are made of Delrin and are tougher than the crappy tools other companies make.
    I got mine from Digikey. https://www.digikey.com/product-detail/en/aven-tools/13016/243-1016-ND/600970
    You should also get a ceramic tip screwdriver: https://www.digikey.com/products/en...ks-picks-probes-tuning-tools/241?k=aven 13222
    I can't remember what exact drives the Pioneer adjustments are but I think the kit and the screwdriver are all you need. Some manufacturers use weird slugs with a wide slot and you have to get special tools or you break the ferrite. I can't find the manufacturer's name for my set.
     
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  15. dr*audio

    dr*audio Fish fingers and custard!

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    Location:
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    The remaining 2 rf adjustments in the front end are T4 and TC4. These are to calibrate the low end and high end of the dial for accuracy. You can do these on stations at the low and high end that you know the frequency. A light touch is important, these adjustments are very sensitive, and you can set the tuning way off.
     
  16. DUALityOFman

    DUALityOFman Active Member

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    176
    Thank you for those pointers. I already ordered that set from Amazon. I'll avoid the parts most likely to cause trouble and stick to the adjustments you recommend. I'll try to remember to post the outcome...will be at least a few days. If you never hear back, either I died trying to adjust it, or I am too ashamed of the outcome to mention it.
     

     

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  17. I LIKE MUSIC

    I LIKE MUSIC Super Member

    The above procedures are good information.

    However, this it how the service manual indicates the procedure to adjust the discriminator. This works for this receiver because it uses ceramic filters for the IF chain and it is just a matter of plopping the discriminator on top of the IF frequency.


    upload_2018-1-10_18-51-14.png

    If your the center tune meter is centered when the receiver is turned off and when the signal strength meter is at its highest when tuning in a station, the discriminator adjustment is likely very close.

    In general, when doing the RF front end adjustments, it can help to use somewhat weaker stations (signal strength meter at less than half scale), This will help reduce the affect of the RF/IF AGC circuits and make your adjustments a little easier to see on the signal strength meter.

    DUALityOFman, when adjusting the inductors (the things that use the hex tool for adjustment), be somewhat gentle, the ferrite slugs can be somewhat fragile. Don't pull the alignment tool to the side.
     
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  18. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

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    Great explanation from dr*audio
     
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  19. DUALityOFman

    DUALityOFman Active Member

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    176
    Thanks for all the guidance. I'll be reading over your notes while it's on the table...just before I pull the lever that raises it up through the gaping hole in my castle roof to try and catch some lightning. Or something like that.
     
  20. john stumpf

    john stumpf AK Subscriber Subscriber

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    Location:
    philippines
    my advice is to stay with basic adjustments on the tuning cap. you REALLY can get things fouled up without a signal generator. i know this as i managed to thoroughly screw up a 1080 fm tuner when i thought i understood. ive since acquired a signal generator and while i dont have a distortion meter or a STEREO signal generator to adjust mpx im light years ahead in the game as at least i can do the front ends with some degree of confidence.the other poster's arent wrong but im just sayin..... before you get carried away tune it from the extreme left to right and note if the needle goes to the end of the scale,if not loosen the pulley set screw and rotate on the shaft repeat as necessary untill it does. the v cap is the "stop" for travel and it shouldl be fully open or closed at the ends of the scale and not over shoot one side or under shoot the other. if it does its possible that its drifted far enough where someone has tried to make the dial agree with the received station frequency.after i botched the job i decided to get a new board on ebay.it took 2 years to find an awe-93. this was two years prior to the signal generator acquisition. they are really scarce.
     
    Last edited: Jan 11, 2018

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