Espey 78 only record Player

[retroaudio]

I obtained an Espey record player from a local antique for a small sum. Its American from I would say around 1944 judging by the dates on the electrolytics. It is 78 rpm only with a magnetic pick up. It works it was relatively easy to rebuild the pick up with rubber and shrink tubing to replace the perished rubber. The volume is good. The motor is also fine. It rotates at the correct rpm and it is not noisy. It needs some lubrication as matter of good practice.

The problem is I have no circuit diagram. The player has horrendous mains hum which indicates smoothing problems. I cant identify the valves they are American. They have lost their markings. There are3 in total and they are all loctal.

I am wondering if Espey ever exported their products to the uk in which case this must have been converted for 230 v mains AC use here. Or has someone brought it back from America and tried to convert it themselves. The one Espey I have seen on YouTube had very little in the way of smoothing caps.

each valve appears to have its own supply via an electrolytic, There is a shared negative to chassis.

The values of the electrolytics are as follows.

30 uF at 450 volts
30 uF at 450 volts
1 has a paper Dubilier electrolytic at 30 uF at 150volts. in parallel sharing the positive terminal of the capacitor

There is then a square high voltage electrolytic value 4 uF

I have worked on power supply stages on valve radios before usually with success but I have not encountered one like this before so I am looking for pointers as to the rationale behind this smoothing set up, I can put pictures up tomorrow if this would help.

Alex

[Herald1360]

There are a few Espey record players in Radiomuseum. They mostly seem to be 117V live chassis designs. Is there a transformer or line cord on yours? Is there any voltage rating indicated on the machine? The 450V ratings on the electrolytics do suggest a 230V supply or at any rate conversion attempt. Does the motor have any useful rating information?

Does the turntable run at the correct speed rather than about 20% slow? If it does, an export model is likely.

Pictures always help.....

[Station X]

Originally Posted by Herald1360

Does the turntable run at the correct speed rather than about 20% slow? If it does, an export model is likely.

The OP stated in post #1 that the motor runs at the correct speed.

Originally Posted by retroaudio

The motor is also fine. It rotates at the correct rpm and it is not noisy. It needs some lubrication as matter of good practice.

Alex

[retroaudio]

Hi I have had another look at this record player this afternoon and the current layout does not correspond with any circuit diagrams I can see. I have been able to identify 2 valves I think as there are some faint markings on inspection .

35Z5 GT
50L6GT

They are both Octal rather than loctal. The third is black and has no markings and a metal casing. This is mounted on a separate plate mounted on the chassis

The motor is 117v ( under the turntable) There are no other identifiers. There is a small mains transformer bolted to the underside of the motor board with no values. The speaker is only about 4 inches and has its own transformer which works.

I am wondering if this conversion has been done badly whether it would be better to put it back to 2 valve 110 volt operation on a dropper transformer. I already do this with an American radio without an discernible deterioration in its operation,


Alex

[Herald1360]

The third valve is likely a 12*** either a triode or pentode with a 150mA heater. You don't mention a top cap....? Maybe a 12(S)J7?

A pic of the underside connections should help decide what it could be, though chances are it will be fine.

The other two are likely identified correctly- they would make perfect sense as rectifier and output in a series string 117V set. Is there a heater dropper resistor there?