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Old 7th Sep 2019, 9:54 pm   #41
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Default Re: “Manky thing” in HMV 2010 model

You could also try changing over the left and right hand +ve leads at the cartridge. If you continue to get sound, albeit perhaps in mono, the cartridge is OK.
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Old 7th Sep 2019, 9:57 pm   #42
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Default Re: “Manky thing” in HMV 2010 model

Posts crossed.

Both channels of the amp work, but there's only a buzz on three of the four leads going to the cartridge. That points to a disconnection between the cartridge and the input to the amp. Might just be tarnishing of the connectors. Try removing and replacing them.
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Old 7th Sep 2019, 10:18 pm   #43
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Default Re: “Manky thing” in HMV 2010 model

Good for you if you want to collect 78s. If that is the case then go for Edward's suggestion of buying a BSR cartridge.

There are plenty of 78s around, even on the Isle of Man - Jurby Junk had hundreds and even though that is long gone I bet they will turn up somewhere. The prices charged for 78 on ebay are mainly extortionate although in the odd mad moment I have to admit to having bought one or two ones that I really wanted. I would generally expect to pay around £1 each from an antiques centre over here. You can get job lots at auctions quite cheaply.

As others have said it sounds as though there isn't a lot wrong with your record player. I am sure you will get it working, and if your wife likes it half your troubles are already over!!

Keep up the good work!
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Old 7th Sep 2019, 10:58 pm   #44
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Default Re: “Manky thing” in HMV 2010 model

Quote:
Originally Posted by Station X View Post
Posts crossed.

Both channels of the amp work, but there's only a buzz on three of the four leads going to the cartridge. That points to a disconnection between the cartridge and the input to the amp. Might just be tarnishing of the connectors. Try removing and replacing them.
Yes, this is what I thought, they did look a little blackened, I’ll fiddle tomorrow.

And then if I can get stereo, I will then track down the volume issue with the help of my step dad, retired electronics guy.

It’s quite fun this, I just wish I knew a little more so thanks to ALL of you guys for chipping in with snippets, I really, really appreciate you sharing your knowledge and experience.

Quite soon I’ll be getting some Roy Orbison Original 45s on it which I just bought in a moment of retail weakness.
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Old 8th Sep 2019, 10:08 am   #45
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Default Re: “Manky thing” in HMV 2010 model

If you are going to use the HMV quite a bit then I think you should change the cartridge for a BSR one. Even though the missing channel may be another fault the low volume is probably due to deterioration of the Ronette for reasons already discussed. Also the compliance of the BSR will be better than the Ronette and will put less wear on your records. Although looking very different to the Ronette the BSR should be a straight swap.

In case you are wondering the logic behind what has been said about the HMV basically working is that the stereo/mono control will connect both channels together "early" in the circuitry. If you get sound from both speakers at the same level with the mono control activated then the fault must be before that which only leaves the connection going from the cartridge to the amplifier or possibly the stereo/mono switch itself. Both of these are easy fixes.
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Old 8th Sep 2019, 10:24 am   #46
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Default Re: “Manky thing” in HMV 2010 model

Checking the circuit diagram shows that the stereo/mono switch is AFTER the first stage of each channel of the amplifier. If there's a problem with the first stage of one channel this would give the symptoms described.

However, before investigating the amplifier, I suggest the OP checks the wiring from the cartridge to the amplifier and repeats the buzz test at the tag board which is probably under the deck. The blue and red wires should give a buzz.

The 47k resistors connect to a 5 pin DIN socket for a tape recorder.
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Old 9th Sep 2019, 10:59 pm   #47
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Default Re: “Manky thing” in HMV 2010 model

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Originally Posted by Station X View Post
Checking the circuit diagram shows that the stereo/mono switch is AFTER the first stage of each channel of the amplifier. If there's a problem with the first stage of one channel this would give the symptoms described.

However, before investigating the amplifier, I suggest the OP checks the wiring from the cartridge to the amplifier and repeats the buzz test at the tag board which is probably under the deck. The blue and red wires should give a buzz.

The 47k resistors connect to a 5 pin DIN socket for a tape recorder.
I still only get one buzz off the red wire at the “other end” , under the deck, so some consistency there.
I’ve taken the plunge and bought a bsr cart off of eBay. Hopefully I’ll be jiving to the king, a pack of 45s I’ve just bought, very soon.
Rock on.
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Old 10th Sep 2019, 1:09 am   #48
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Default Re: “Manky thing” in HMV 2010 model

Sounds like TR101, or whatever its sister one is labelled as on the silent channel, may have tin whiskers. Might be worth isolating the transistor from its metal heatsink then briefly testing.
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Old 10th Sep 2019, 7:45 am   #49
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Default Re: “Manky thing” in HMV 2010 model

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Sounds like TR101, or whatever its sister one is labelled as on the silent channel, may have tin whiskers. Might be worth isolating the transistor from its metal heatsink then briefly testing.
If the new cart doesn’t miraculously cure it all, then it’s some proper diag I’m going to be into.

When you say isolate do you mean extricate from heatsink or isolate the transistor by desoldering ?

Btw I’m also assuming, that so long as I stay clear of anything around or on the mains side of the transformer etc that if I touch the wrong thing I’m not going to get a horrible shock ? Or at least not a lethal one ?
Plainly I’m not going to be fingering everything whilst live, I’ll be using the meter but, just in case.
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Old 10th Sep 2019, 8:34 am   #50
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Default Re: “Manky thing” in HMV 2010 model

Where 'tin whiskers' are suspected, temporarily remove the heatsink, especially if a pair of output transistors bolted to metalwork via a cooling clip is/are used. That way, if one device has an internal s/c to it's metal case, it will be easy to prove. No need, at this stage, to desolder anything.
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Old 10th Sep 2019, 9:37 am   #51
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Default Re: “Manky thing” in HMV 2010 model

Notarfff.

You could try a buzz test at the tape socket with the switch set to stereo. I'm not saying it will work, because there'll be one less stage of amplification available and consequently the buzz, hum or click may be low in value or non-existent.

There should be a buzz from 4 of the 5 sockets if you insert say a straightened out paper clip into each socket in turn whilst holding it in your hand. A good result here will confirm a problem with the first stage.

You could also try the test described in post #41 which will confirm the cartridge's viability one way or the other.
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Old 10th Sep 2019, 8:49 pm   #52
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Default Re: “Manky thing” in HMV 2010 model

There is a lot of information on the net about tin whiskers in transistors. Basically they grow from the inside of the metal case and end up touching the transistor inside and shorting it to the case. If the case is on a heatsink then it will short out the transistor. Some transistors have a fourth lead connecting the case to the chassis. Sometimes a temporary cure can be made by snipping this lead. Sharply tapping the transistor can dislodge the whiskers temporarily and it might be worth trying that.
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Old 10th Sep 2019, 10:16 pm   #53
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Default Re: “Manky thing” in HMV 2010 model

Thanks fellas, I’m learning so much from you guys, I had to work late tonight, but I’ll be on it tomorrow.

When this thing works I’m throwing a party, you’re all invited, bring some 45s though I don’t have many.
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Old 13th Sep 2019, 8:19 am   #54
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Default Re: “Manky thing” in HMV 2010 model

I’ve cleaned, fiddled, and I think now broken the ronette cartridge, my new BSR arrived yesterday so I shall be hopefully fitting that tonight. I’m still frustrated and can’t quite believe the ronette is broken but it is 55 years old, and has been abused over the last 20 years so I guess it’s not surprising really.

I’ll keep everyone posted. If this doesn’t fix all my ills, then it’s out with the multi meter
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Old 13th Sep 2019, 11:12 am   #55
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Default Re: “Manky thing” in HMV 2010 model

Make sure you observe the colour coding on the cartridge leads. A misconnection there will give you no sound, mono sound or out of phase/distorted sound.
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Old 13th Sep 2019, 8:55 pm   #56
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Default Re: “Manky thing” in HMV 2010 model

Quote:
Originally Posted by Station X View Post
Notarfff.

You could try a buzz test at the tape socket with the switch set to stereo. I'm not saying it will work, because there'll be one less stage of amplification available and consequently the buzz, hum or click may be low in value or non-existent.

There should be a buzz from 4 of the 5 sockets if you insert say a straightened out paper clip into each socket in turn whilst holding it in your hand. A good result here will confirm a problem with the first stage.

You could also try the test described in post #41 which will confirm the cartridge's viability one way or the other.
Wel, I finally followed Graham’s advice and i do indeed get a buzz from 4 of the 5 sockets.
The buzz from the two sockets that output to the left speaker are healthy and loud, the other two, which go to the right speaker are there but both very quiet. And obviously the fifth does not buzz at all.
So I’m guessing therefore that this problem lies a little deeper ?
Everyone’s advice greatly appreciated.
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Old 13th Sep 2019, 9:31 pm   #57
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Default Re: “Manky thing” in HMV 2010 model

Is the sound the same level from each channel when the mono button is pressed? I wonder whether there is a problem with the switch itself.
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Old 14th Sep 2019, 11:13 am   #58
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Default Re: “Manky thing” in HMV 2010 model

Looks like there's more than one fault with this player.

Time to get the meter out, take voltage readings and compare them with the service sheet. The great advantage of a stereo amp is that you can compare the readings of the two channels.
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Old 14th Sep 2019, 9:04 pm   #59
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Default Re: “Manky thing” in HMV 2010 model

I will do, I’ll post any findings
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Old 22nd Sep 2019, 1:06 pm   #60
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Default Thanks, StationX,PaulR,Edward,Ben and others

re: my HMV 2010, Garrard AT5 with the non-stereo, no volume, etc.

Thanks to all of your advice and guidance i'm seeing success.

Bought a BSR SC12, after fiddling with that for a while, fitting, balancing etc. I've now got bags of volume, really pleasing.

still not got proper stereo, but mono is fine.

one further question: if i want to run some test on the circuitry, to figure out whats wrong with one channel possibly, obviously i need power on but do i need to run the thing and put some input through it in order to diagnose correctly. or should i be seeing correct voltages regardless of input?

Thanks all once again !!
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