Fidelity Record Player. Wrong fuse in mains plug.

[Station X]

Looks like slidertogrid has the motor needed. Two white leads supplying AC to the bridge rectifier.

[Viscount]

yes i thought that maybe a rectifier there ,will change that as advised,and the cap ,so im asking what voltage tapping am i looking for regards the motor?obviously not the 90v version

[Station X]

It's not a tap, it's a separate winding. Generally around 18V which fits in with the 15 VDC? smoothing capacitor.

[Viscount]

Originally Posted by Station X

Looks like slidertogrid has the motor needed. Two white leads supplying AC to the bridge rectifier.

thankyou station x invaluable advise as ever

[ms660]

I would also check what output transistors is uses, they might not be suitable for a B+ derived from an 18 Volt motor winding like one of the integrated circuit amplifiers. The output transistors can suffer from tin whisker syndrome.

The schematic for the HF42 shows 9 Volts AC across the rectifier input, the HF45 shows 17 Volts AC, the schematics are for IC amplifiers.

Lawrence.

[Station X]

See post #16 in the current thread.

Originally Posted by Viscount

has transistor line up BC157/BC148/AC176/AC128

[ms660]

18 volts in will be approx. 24 Volts out.

Lawrence.

[ms660]

It looks like a transition from the single ended transistor output to the TBA800 used in later record players.

Lawrence.

[Station X]

Originally Posted by ms660

18 volts in will be approx. 24 Volts out.

Lawrence.

Could be a lower input voltage then as the smoothing cap appears to be rated at 15V.

I hardly think BSR would have made more than one motor type with a winding for a transistor/IC amplifier.

[ms660]

Originally Posted by Station X

I hardly think BSR would have made more than one motor type with a winding for a transistor/IC amplifier.

If they only did one motor type the secondary must have had a tap or two separate windings to suit the HF42 or the HF45.

Lawrence.

[Station X]

HF42 is a mini player and I'm not sure whether it uses a BSR deck, although the motor is similar.

There are Red and White leads from a winding on the motor to the amplifier. The OP's player has two White leads.

https://www.vintage-radio.net/forum/...d.php?t=161667

EDIT.

I see that my HF42 uses an IC, as does that on rm.org, but the service sheet shows transistors. Bit of a mine field.

How can we help the OP? Only clue seems to be the 15V ?? smoothing capacitor and two white wires from the motor. I can't find a service sheet to match his amplifier.

[Heatercathodeshort]

In all my many years in servicing record players I have never seen anything like it! That looks as if actual flames have burnt the wood motor board. That requires very careful investigation.
I suppose if the bridge rectifier went S/C and the record player was left on for a very long period the motor could overheat but that is a total burn out. Take care, John.

[slidertogrid]

The motor I have has come from the later Fidelity with the IC amplifier. We need to know if the LT winding on this motor is suitable for the earlier player voltage wise. I assume your player has all speeds 16 33 45 78? My motor might only have 33 and 45 as the later players often didn't have all speeds. I will have to check.
If so you will have to swap the armature over from your motor as the stepped part of the spindle will be wrong. I will have a look tomorrow. In the meantime does anyone have the two players circuit diagrams to hand to see if the LT winding is suitable?
Rich.
Ps I have replied to your PM.

[ms660]

Originally Posted by Station X

HF42 is a mini player and I'm not sure whether it uses a BSR deck, although the motor is similar.

I won't give a link but there's an HF42 motor (TP8 series) up for sale on a website that has BSR stamped on it.

Lawrence.

[Techman]

Originally Posted by ms660

I won't give link.

You're allowed to if it's to help out with a component part - so long as you don't discuss the seller.

Is this the one? If not, post the link to the correct one.
https://www.ebay.co.uk/itm/184855231...IAAOSw~XRg0H9o

[ms660]

Yes, that's the one.

Lawrence.

[lesmw0sec]

Originally Posted by Restoration73

Any protection offered by the fuse is secondary, its purpose is to protect the supply cable.

I would suggest that a better description might be that the purpose of a fuse is to break when the current exceeds a dangerous limit from any cause. I doubt if anyone is concerned about a few feet of twin flex, but it might be a problem if it or another component catches fire.

I recall being taught in college that the purpose of the fuse was to protect the power station...

[Hartley118]

My experience of small induction motors driving extractor fans suggest that a stalled rotor is unlikely to cause serious overheating. Such stalling is common in badly maintained extractors and it’s rare that it results in smoke.

In this case, the motor is also serving as a transformer, with the attendant risk of a short on the secondary, which is much more likely to release smoke. So I would certainly be looking for a shorted component in that secondary circuit.

Martin

[ben]

I agree with Martin. Whilst there could conceivably have been some kind of insulation breakdown in the motor's stator coils, I doubt that would have caused such a burnup. I have, however, seen these motor windings get very distressed with a shorted rectifier as load.

First thing to do it replace the bridge and the associated cap, then when a suitable replacement motor has been fitted connect with ammeter in series to see what current is being drawn. It's not beyond the bounds of possibility that the output germanium transistors may be leaky or shorted.

[Techman]

I've said it before, that in the event of a fault like this, the amplifier and its associated rectifier need thoroughly testing before even thinking about replacing the motor/transformer. It may well be that the output transistors are failing and have taken out the rectifier, which in turn burnt the motor windings. In the event of not having a current limited bench supply, my suggestion, which I've made on several occasions, is to make up a supply of the required voltage with cheap Poundland batteries. An ammeter should be placed in the supply line and the current being drawn monitored over time, as it's quite possible that the current will increase over time with bad and leaking transistors. The rectifier should be checked with a meter for shorted diode sections - this should be left out when testing the amplifier on a power supply or batteries.

That motor is certainly bad and I've never seen anything that extreme before in a record player. A 3 amp fuse wouldn't have saved the motor windings, but I can't help thinking that by the time it had got to that 'fire' stage, that the current being drawn by that time might have just blown a 3 amp fuse if one had been fitted - best to fit a 2 amp or 1 amp fuse in the plug if you can...it's unlikely that a 1 amp fuse would blow with switch on surge in a player like that.