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 Only one speaker working.... amongst other concerns?
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 Return to top of page · Post #: 1 · Written at 4:59:15 PM on 22 October 2016.
Big Ad's Gravatar
 Location: Melbourne, VIC
 Member since 22 October 2016
 Member #: 1994
 Postcount: 5

Hi all. Just found this site. Very cool. Ive just been given a HMV Rhapsody Stereophonic player and I love it and would like to use it.

I'm a mechanic by trade and have some basic electrical knowledge. The wiring diagram ive found for this unit doesnt have wire colours on it so I'm out of my depth.These are some things I would like some help with if possible.Any/All help very much appreciated Smile

The unit swithes on,lights work,radio works well and receives heaps of stations well.
Only left speaker works!! Ive tested both speakers and both ok. So right channel no good. It worked intermittently when hitting cabinet and cranking volume a few times but now no working at all except for a faint output? Volume,tone and bal knobs seem to work correctly. There is a grey wire hanging loose in cabinet that seems to have something to do with radio coil?

Record player does work,it plays music,the start/auto controls and speed control work and the tone arm seems to return home correctly when switching to auto return or when it reaches the end of the record but it wont move to play position automatically when switching on?

The auto load function doesnt seem to work either? The record size detector, over arm and stacking spindle dont seem to do anything?

Any general info or known specific problems/fixes for these units is greatly appreciated!


 
 Return to top of page · Post #: 2 · Written at 5:19:52 PM on 22 October 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6686

So right channel no good. It worked intermittently when hitting cabinet and cranking volume a few times but now no working at all except for a faint output?

Some of the usual suspects for that symptom:

Dry solder joint
Cracked PCB track
Dodgy output transformer (if circuit uses one)
Bad capacitor(s)
Faulty volume or balance potentiometer

The wiring diagram ive found for this unit

Does that diagram mention a model number?


 
 Return to top of page · Post #: 3 · Written at 10:33:49 PM on 22 October 2016.
Big Ad's Gravatar
 Location: Melbourne, VIC
 Member since 22 October 2016
 Member #: 1994
 Postcount: 5

Thanks heaps for reply GTC!
A few things there I could check myself at least.

Im thinking of cleaning circuits down with some contact cleaner and give the wires a gentle wiggle etc...

There seems to be only one transformer in unit.

I was questioning the volume pot as it played up when turning it but may have been coincidence?

The BAL pot seems to work a bit different than expected. By that I mean turning it from half way to full left, the left channel gets louder as expected but a very faint output is heard in right channel still.
Turning from half way to full right, nothing happens in right channel except for the aforementioned faint sound but sound in left channel stays at the same level? I'm wondering from factory weather the BAL pot was meant to shift ALL sound to the left or right channel when turned fully in either direction OR is there a "base" level of sound in each channel regardless where knob is turned? Either way right channel is a no-go .

The diagram is for a MODEL T8. The PDF its in is titled Model T8-49


 
 Return to top of page · Post #: 4 · Written at 11:41:20 PM on 22 October 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6686

Okay, we've discussed that model before, here: https://vintage-radio.com.au/default.asp?f=1&th=930

As you'll see, the possibility of "cancerous" germanium transistors is raised there.

Regarding: "There is a grey wire hanging loose in cabinet that seems to have something to do with radio coil?" ... by 'radio coil' do you mean the coils on the ferrite antenna?


 
 Return to top of page · Post #: 5 · Written at 12:27:09 AM on 23 October 2016.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2154

With the volume pot, try loosening it from the chassis then spray contact cleaner or even wd40 into it. then tighten it up again it maybe that its a bit dirty. otherwise do a recap and check all resistors and as above.


 
 Return to top of page · Post #: 6 · Written at 9:09:51 AM on 23 October 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5254

I think we do not need to go shotgunning here. Remember there are two amplifiers and they are the same. One does not interfere with the one that is working.... because it is!

That is the one to provide reference voltages etc. to fix the other one. The problem could be as simple as a wire break on the pick up head. or a dirty switch if it has a radio. And always, look for signs of tampering, there are those who think they know what they are doing & I have wasted a lot of time fixing up there efforts.

The turntable is mechanical and its old. The major cause of problems with them is lack of attention, resulting in grease soaps drying out and hardening, then jamming things.

Marc


 
 Return to top of page · Post #: 7 · Written at 10:12:50 AM on 23 October 2016.
Big Ad's Gravatar
 Location: Melbourne, VIC
 Member since 22 October 2016
 Member #: 1994
 Postcount: 5

Thanks again, that link GTC is where I found the manual before. Smile

The grey wire issue - there is a little black with 3 red stripes diode, mounted just above the ferrite coil thingy that is related to the radio receiver.

A bare copper wire from windings on coil goes to the left side of diode. The grey wire from right side of diode is sitting on the bottom of cabinet,is about a foot long and has a spade terminal in the end of it?

The centre black wire appears to be just soldered to the little mount for this diode. The mount is screwed/earthed to chassis and the other end of black wire goes up to upper facsia and is earthed on the underside of the "SOLID STATE" badge thread!

I'm going to remove chassis and inspect/clean everything. I'll check the pots and switches as stated. Marcc by pick up head you mean the stylus yes? Do they "read" in stereo?


 
 Return to top of page · Post #: 8 · Written at 9:45:01 PM on 24 October 2016.
Big Ad's Gravatar
 Location: Melbourne, VIC
 Member since 22 October 2016
 Member #: 1994
 Postcount: 5

Fixed it! Smile I removed chassis from table and basically inspected everything by eye for anything obvious e.g. burnt cap etc... couldnt see anything wrong so just flooded everything with co cleaner particulary the volume pots which felt real gritty at first. Tested and both speakers and all functions now working! I'm stoked.

The grey wire appears to be the wire that connects to the external antenna if its needed!?

As stated in a response from Tallar Carl , is it ok to use a spray like INOX sparingly in the pots and switches?

As far as the turntable ive cleaned and lubed everything, it all works smoother and I can see how some functions work but I cant tell whats causing the auto function to not work? Any advice or specific knowledge appreciated. Thanks again.


 
 Return to top of page · Post #: 9 · Written at 12:04:45 AM on 25 October 2016.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6686

is it ok to use a spray like INOX sparingly in the pots and switches

Inox is a lubricant. You don't want to leave a film behind when cleaning those components.

Best to use a purpose made product such as this: http://www.crcindustries.com.au/products/cleaners/co-contact-cleaner


 
 Return to top of page · Post #: 10 · Written at 12:20:24 AM on 25 October 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5254

What breed of turntable is it? British Sonotone BSR: Garrard; Colaro; who knows? BSR spare here has Stop; Start & Auto you push the lever further up to auto & release it & it engages the drive gear.

You did remove the transport clamp, on the tone arm, didn't you.


 
 Return to top of page · Post #: 11 · Written at 9:32:18 PM on 26 October 2016.
Big Ad's Gravatar
 Location: Melbourne, VIC
 Member since 22 October 2016
 Member #: 1994
 Postcount: 5

Yeah I used contact cleaner but was just wondering about the spray lube. I wont use it.

Yeah Marcc I removed the clamp Smile I'm just going to have to try and nut it out myself!?
The table is a BSR Model A10.
I saw a clip on you tube of a guy demonstrating how the auto load function works and mine doesnt do it.? I'm hoping its just needs a good servicing but ill let you know. Thanks again


 
 Return to top of page · Post #: 12 · Written at 11:40:55 PM on 26 October 2016.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5254

BSR is not usually a complex turntable. There is one particular model/s that welds. the platter to the shaft, if its left a long time.

Marc


 
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