Almost working AMI Rowe R-83

[wyofletch]

Greetings,



A caveat before I begin: This is the first project like this I have ever undertaken and I am not by any stretch of the imagination a "handy man"...



I inherited a Rowe AMI R-83 jukebox a few weeks ago. It has been sitting in a barn for 20ish years and to my mild surprise it powered up, selected records and played fairly well. It played the records pretty slowly but after cleaning and lubricating the table, post and pivot points that seems to be fixed.



I have three problems that are vexing me:



First, when I initially powered it up and played a record it would on occasion get much louder and very "tinny" (lots of treble) there was no rhyme or reason for this that I could tell. After giving the box a good cleaning (unplugging all the fittings, cleaning the connections and reseating them) the volume fluctuation is gone but now it is pretty quiet and the volume doesn't change much when I turn the knob.



Second, the sound is very fuzzy. I have purchased several new 45s to play and even the brand new ones sound fuzzy.



Third, the juke will play most 45s just fine but, on occasion, it will kick one out it has been playing fine in the past. The machine makes clicking noises, almost like there is too much input and then the record gets rejected.


The tone switches on the amp don't seem to do anything at all. If I switch it to additional bass or treble nothing seems to happen. The switches are also pretty stiff and hard to move.


I have done the following:



Replaced the cartridge and the stylus

Unplugged, cleaned and reseated all connectors

Cleaned all terminals where wires are connected.

Checked the speakers in the main cabinet for damaged cones etc.

(if someone could tell me how to get into the lower cabinet where the bass speakers are, I would really appreciate it).



The tone switches on the amp don't seem to do anything at all. If I switch it to additional bass or treble nothing seems to happen. The switches are also pretty stiff and hard to move.



I would GREATLY appreciate any help that is offered. I would love to get this thing singing sweetly in the basement.

[robnyc]

Fletch, the clicking-rejecting is likely the "no record reject" contacts on the tonearm. This is a pointed screw that completes the reject circuit if the arm lowers to the point were the adjustment assumes there would be no record. It is right under the arm and has two flexible wires connected. If a warped or dished record is played these contacts may touch intermittently causing the amp to mute sporadically and jogging the changer motor till it finally carries over and rejects the record. I always eliminated them -they just add drag.

Did the sound change after you replaced the cart or only after you worked on the amp. these later Rowe amps were notorious for poor connection at "stake" connectors. Very often reflowing all the solder connections there will restore operation.

One test I always do on any electronics after service is to place the item where you can gently flex the boards while it is playing. Since the voltages are low you can use a bare finger, but a rubber glove or plastic pen is best. Poor connections are often revealed this way.

The machine is 38 years old, subjected to much heavier use than a home phono along with what sounds like poor storage conditions. Even if the above amp suggestions work out it may only solve things temporarily. It probably is time for a major rebuild of the electronics.

I can't recall if Rowe used foam surround for the speakers, but if so, they will surely have disintegrated by now and cause poor sound. In any case, storage in moist conditions will ruin speakers quickly. You can try hooking up some known-good externals to see if the sound improves.

Hopefully, Alan Hood will chime-in on this topic. He has a lot more experience on these later models.

RobNYC

[Ron Rich]

Guys,
On the warped record switch, I also usually eliminate those UN-flexible ( anymore) wires too--but also run the "adjustment screw" either up or totally remove it, as if/when it touches the pad, it can cause skipping--
Switches on the amp., can, and should be "cleaned", with Deoxit-5 as per directions on the can !!
As pointed out--that amp is LONG over due for a professional rebuild --NOT just "a Ka(r)p kit" ! Another problem that plagued that series Rowe, was the fact that they used round "headers" and flat contact surfaces in the pins that connect to the headers. I remove EACH pin from the
"plug", clean it with Deoxit, "reform it" to add pressure --reinstall it in the housing. Also I clean the round header pins with Deoxit, after re-flowing ALL solder joints. Note--any pin on either the header, or housing that is dis-colored/burnt, MUST be replaced !!
Ron Rich

[wyofletch]

Thanks for the quick replies! I think you guys might be spot on with the reject circuit on the tone arm. I will adjust it and see if that works.
The sound changed after I cleaned the connectors. I cleaned them all and plugged them back in. When it seemed to help the fluctuation of volume I tried to adjust the bass and treble and that is when the volume decreased. I did Deoxit the switches on the amp.

I am not opposed to sending the amp in for a professional rebuild, I just wanted to make sure I was addressing the issues I could before I took that step.

Does anyone know how to access the lower speaker chamber so that I can check the foam seating of the bass speakers? Crazy enough, there aren't instructions to do that in the manual.

Thanks

[Ron Rich]

Rowe Manuals suck in that regard--just gotta start "un-screwin'"----take photo's ! Look at the parts section--
Ron Rich

[Deleted]

Aug 23, 2017 20:36:20 GMT wyofletch said:

Thanks for the quick replies! I think you guys might be spot on with the reject circuit on the tone arm. I will adjust it and see if that works.
The sound changed after I cleaned the connectors. I cleaned them all and plugged them back in. When it seemed to help the fluctuation of volume I tried to adjust the bass and treble and that is when the volume decreased. I did Deoxit the switches on the amp.

I am not opposed to sending the amp in for a professional rebuild, I just wanted to make sure I was addressing the issues I could before I took that step.

Does anyone know how to access the lower speaker chamber so that I can check the foam seating of the bass speakers? Crazy enough, there aren't instructions to do that in the manual.

Thanks

Hello wyofletch,

Sorry but you did not leave your name.

On the R-83 they did not use foam surrounds on the bass and high range speakers, the bass will be fine just inspect the high range speakers. Sadly every mid range speaker I have looked at on the R-82 & R-83 jukboxes (just under the keyboard has a rotted foam surround) these foam surrounds can be replaced.

First of all make up a test volume control for the amplifier (you could use the existing plug) using a 10k log control connect pins 1 & 5 to one end of the pot, connect pin 3 to the wiper. Using a test control eliminates any internal wiring issues.

I tend to remove switches from the pre-amplifier if they are stiff and strip them down to clean the contacts, I use a pencil rubber (eraser) for this.

Check to see if the two small lamps in the volume circuit (DS1 & DS2) are still both connected, the laps fitted had poor leads and tended to rot off.

The 13 pin jumper connection is not without faults dry joints (cold joints USA) on the header pins are an issue also the same can be said for the two four pin connections that supply the voltages and signals from the pre-amplifier to the driver boards.

Assuming you are in the USA Ron would be a good contact to send your amplifier for refurbishment.

Regards
Alan

Alan Hood
ami-man
UK 

[wyofletch]

Sorry for the delayed response... traveling, and my name is Andy.

The suggestions to back out the screw and/or disconnect the reject sensor worked great.

The amp # is: 601-07438

I am in the process of going through the suggestions above for cleaning and checking the joints, voltages and pins. I will update as I proceed. I have never done anything like this before so I am scared sh*tless but you never know until you try...

A more elementary (and hopefully more simple) issue: When the records start playing the stylus drops a little deep in the record (cuts off about the first 10-15 seconds of the song) is there an easy adjustment for that?

Here are a couple of pictures of what I am working with:
The second picture shows a couple of silver wires that are cut. They are attached to  "common" and "phono spkr vol." Am I right in assuming I can just disconnect those?

[Ron Rich]

Andy,
I don't know where them thar wires go ??--- all you need is the red and black from the volume control there--red is "hot" black is common(to both reject and VC)--white should come from the "cancel", or reject switch on the cabinet rear. Ron Rich

[robnyc]

" When the records start playing the stylus drops a little deep in the record (cuts off about the first 10-15 seconds of the song) is there an easy adjustment for that?"

Before checking adjustments or faults, make sure that the tonearm wires are not binding or biasing the arm. This will not normally be a problem, but if the connection to pickup socket on the side of the mech have been repaired at some point, sometimes the "technician" didn't take of proper cable dress. As i suggest earlier you may as well remove those no-record reject wires.

If that checks out make sure the actual setdown position is correct. Stop the mech just as the arm is setting down -but not on the record. gently push the arm outward. It should be hard against the cam and the stylus thus directly above the lead-in grooves. If the arm has drifted inward check the following: As the cam guides it toward the setdown position one of the pins extending down from the rear of the arm assembly is held against the cam profile by a copper spring inside the cam. These sometimes break and allow the arm to drift inward.

You can see it here: www.ebay.co.uk/itm/ROWE-AMI-JUKEBOX-1100-1200-MECHANISM-TONE-ARM-CAM-PART-NUMBER-2-10892-01/321218883580?hash=item4aca232ffc%3Ag%3AhuAAAOxy3hJSSFAQ

Check that there is no sideways 'slop" of the tonearm cam.

There are two metal 'fingers" extending upward from the mech deck which interact with the trip magnet on the arm assembly. These are an antiskate gimmick and adjusted by bending with a needle-nose pliers. They are tricky to set "just right" and can affect biasing differently at the lead-in vs the tripoff points. They should not be tampered with unless all previous checks are Ok but have not solved the problem.

Properly set up and using a good compliant stylus this arm will track at 1 gram. I always set them for 2gm for commercial service. For a simple post bearing and fairly massive arm assembly, these are really excellent arms for a jukebox.

"The second picture shows a couple of silver wires that are cut. They are attached to "common" and "phono spkr vol." Am I right in assuming I can just disconnect those?"

Those are something left over from some much older type of installation. Do check to be sure that the speakers are correctly connected at the transformer package.

Rob NYC