Repairing a Sharp Optonica RP-117H

This turntable was bought on Ebay “for repair”. The first problem was that the turntable tray was loose and wouldn’t retract or come out. On removing the covers, a shield over the tray motor and the motor itself it was obvious what the problem was:

Broken tray gear wheel

The gear wheel is split, and has dropped off the motor drive. Here is a close-up of the gear:

Closeup of gear

Because the gear had shrunk a little (probably why it cracked), simply epoxying it together at the crack didn’t work: this made the hole too small and prevented the gear from going back on to the drive shaft. I carefully bored the hole out a tiny amount, then used epoxy to glue the crack and the gear back onto the shaft: I clamped it there for 24 hours.

Next problem was a broken belt for the platter itself: to reveal this involves removing a plate underneath the turntable tray:

Broken belt on motor

The belt had disintegrated, leaving a rubbery mess over the turntable and the motor capstan – removed fairly easily with rubbing alcohol. I ordered a replacement belt, and fitted it by feeding it through from the top of the turntable. It was a bit fiddly, but I’d read somewhere it was a nightmare – I didn’t find that.

Now the turntable tray moved in and out, and the turntable turned. The next problem was that the stylus trays were not moving. These trays move linearly across the deck. There is a clever mechanism with worm gears and a slotted metal disk and opto-transistors that move and detect where each stylus arm is. Here is the mechanism:

Stylus trays mechanism

Just visible at the back of the mechanism is a rubber belt – of course this turned out to be worn and was slipping on the motor and not moving the mechanism. I replaced it with a rubber belt I happened to have in my parts box and fit very nicely. Now the whole mechanism worked. Here is a video of it in operation, showing the switchover to Side B from Side A, which involves the turntable motor reversing direction.

The fitted stylii are by AudioTechnica. The Sharp part number is STY133.

AudioTechnica Stylus

Although the turntable now works, it initially played several LPs without issue, it has now developed a random periodic click/thump, almost as if the record is scratched. This is a little peculiar and hard to understand. To be continued ….

Sharp Optonica RP-117H and Sony CDP-X555ES
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35 thoughts on “Repairing a Sharp Optonica RP-117H

  1. Not bad…..for the year 1980.May be this is the father of CD players…..I have at home Sharp rp 107 fully working (looks the same like this on the picture) But i don’t now – is a belt drive or direct drive,because just a little drags speed..can you help just a little..Thanks

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    1. It’s a belt-drive turntable. I recommend lubricating the ring that clamps down on top of the record when the unit shuts – if that sticks at all it has undesirable effects.

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  2. Hi,did you now the correct width and the diameter of the belt for this sharp.To buy from my country.It’s faster way.Thanks and regards from Bulgaria.Outer way i must buy from E-bay and must wait around 20 days……

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  3. HELLO
    I am looking at getting my hands of one of these one of these days too…
    However the one I am looking at my be in dier need of changing both stylusses as well as the sensors for track recognition…
    The tray still works and it does play both sides, but you cannot program the tracks…
    Any ideas on the work involved in arranging that as well as where to get the necessary parts for it ?
    Any general recommendations before putting it to use ?
    thanks in advance

    Dominique

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    1. Hi Dominique,

      The stylii are quite easily found for sale, but cost around $40 each. New belts are available on Ebay.

      I think the logic board for programming the tracks is at the front, behind the switches themselves. I took mine off to see if I could find out why the lights/leds for tracks 1 and 5 (only) weren’t illuminating. There was nothing obviously wrong, but I cleaned all the contacts etc. anyway, put everything back, and they still don’t work! If you can’t programme any track at all, then I suppose the chip may be fried, or there are some very dirty contacts.

      Julian

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  4. I’ve got a Sharp RP-117 that I’m interested in selling to someone to refurbish/part out. (Haven’t had a chance to test it, as all my old albums are buried at my Dad’s house!)
    Let me know if you’re interested!
    -Jesse

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      1. Hi, sorry to hear about your unit … mine is not for sale, as it’s in use πŸ™‚ They do come up on Ebay from time to time, if that helps. Julian

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  5. Nice pictures. They really help. I have your gear problem and may try your solution – but mine is broken in one place and cracked one tooth over. I don’t know where to find parts, or even part descriptions. I did find a service manual, but it looks like what I would need to order is the whole gear assembly (ngerz0004afzz), and everywhere I look, they are not in stock. Where did you order parts?

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    1. Hi Dan,

      The only parts I bought were drive belts, which are available e.g. on ebay. I believe that the toothed gear is NLA. I wondered whether one could be made on a 3D printer? Otherwise the only option s to try a repair or find a parts unit.

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  6. I had the same problem with the gear .. I glued it back with epoxy steel and than made a new tooth with a file .. Thanks for all those info !

    Stef – Montreal

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  7. Over a year since the last post, but now I have an RP-117 that I am trying to nurse back to life. I have found replacement gears which makes that part of the job easier, and I have purchased a new belt for the platter, but I just can’t seem to figure out what to remove to install it. I saw some great Pics, but not enough to know what I should be doing to open it up enough to install that platter belt.

    I have also looked for a shop manual to help, but nothing yet.

    Any advice would be appreciated.

    George

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    1. I have a copy of the shop manual – email me directly if you want it.

      Putting the belt on is a bit fiddly. It doesn’t require that you completely disassemble the unit. With the unit upside down, and the tray out, I was able to place the belt over the platter, and pull it over the drive capstan, using a long curved dental pick.

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      1. Thank you for the response and the advice.

        I have removed the black plastic that covers the platter area (on the tray), but did not remove the tray. I tried to get the belt in place, but I simply don’t think I have exposed enough to get the job done. I have tried to minimize what I take apart in this process.

        In my effort, I have not go to the point of exposing the under part of the platter (as shown in your pix).

        If the shop manual contains instructions for just what parts/screws to remove to expose the underside of the platter, that would be helpful. I am happy to cover any costs associated with passing that along. What is the best way to make direct contact? can you see my email address?

        The belt seems much shorter than it should be, but maybe it is designed to be stretched (I was reluctant to try to stretch it too far and break it).

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  8. George Merrill :
    Thank you for the response and the advice.
    I have removed the black plastic that covers the platter area (on the tray), but did not remove the tray. I tried to get the belt in place, but I simply don’t think I have exposed enough to get the job done. I have tried to minimize what I take apart in this process.
    In my effort, I have not go to the point of exposing the under part of the platter (as shown in your pix).
    If the shop manual contains instructions for just what parts/screws to remove to expose the underside of the platter, that would be helpful. I am happy to cover any costs associated with passing that along. What is the best way to make direct contact? can you see my email address?
    The belt seems much shorter than it should be, but maybe it is designed to be stretched (I was reluctant to try to stretch it too far and break it).

    I sent you the manual by email.

    Julian

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    1. What is the size of the belt for the turntable platter? I have read different sizes online – use FBM 21.4 or HBM 20.0 or? The manual says part is NBLTH0093AF00 but I cannot find the size of it.

      Thanks!

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      1. I don’t know the size in inches – I simply ordered a belt from a seller on Ebay, advertised as being for the RP-117H and it fitted perfectly.

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    2. Hello Julian,

      My first repair was working for a while, an now is seems to be dead again….but that is another story.

      I finanlly attacked the 2 “repair” units a bought a few years ago, new drawer gears, and a new platter belt…and the drawer now opens and closes and the platter turns. In fact, I get the first 1 or 2 tracks on the record, and then it simply stops.

      Any ideas?

      Thanks and Happy Holiday’s,

      George

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      1. Hi George … my guess would be something wrong with the cartridge shuttle mechanism … perhaps it is binding? When I looked at mine, it appeared to be quite delicate, so perhaps there is some foreign body blocking the travel, or a part that has come loose?

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  9. Same here…ordered off eBay and it worked fine. At first I thought is was a little small, but it turned out to fit well.

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  10. Hi There,

    I have one of these with an interesting problem. First it stopped mid playback and then would load a record but not spin. Then after a rest it would load , spin but not engage the sylus, and now it loads and pretty much does nothing…the belt seems to be intact….any ideas?

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    1. I’d suspect the shuttle mechanism that moves the stylii across the record – perhaps one of the caddies is stuck, or one of the microswitches has failed? I’m no expert, but that’s where I would look first πŸ™‚

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      1. Thanks JB, how do I check the caddy situation, are they locked in position until used or can you move them to determine if stuck…the microswitches are the ones that are clicked into position by the drawer closing are they not? πŸ™‚

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      2. I think they are locked in position. The best way to find out what is going wrong is to remove the cover from the unit, load an LP on the platter, and see what happens when you press Play.

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    2. Hello Andrew,

      Did you ever figure this out?

      I am working on two units right now, and after installing new drawer gears and platter belts, both units start to play (either side) and then simply stop. I will open the unit and see what is going on when that happens, but I was curious if you had any luck repairing the issue.

      George

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  11. Hello, I’ve got problem with RP-107H that works great but I can’t programme playing tracks – APMS function fail. I’ve found complete service instruction but I haven’t idea what seems to be wrong. Do you guys solve this problem already?

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  12. Hi JB, stumbled accross this post and wondering if I may ask some questions. I am trying to find the 33 and 45 rpm variable potmeters. I cannot seem to find these. Where can I find these exactly? I found the service manual and it is not that clear to me unfortunately. My RP103 is in perfect working condition, only spins a bit too fast.

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  13. I no longer have my unit, but my recollection is that this board and those pots are evident and accessible once you remove the cover of the player.

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