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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment.

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Old 23rd Feb 2021, 1:20 pm   #1
AnGSB8s
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Default Steepletone 5002D Speaker Wiring

Hi
I am new to UK Vintage Radio website.
I read with avid interest the May 2020 Thread entitled 'Steepletone 5002D' started by member AlanMK71 with speakers containing Disco lights!
https://www.vintage-radio.net/forum/...d.php?t=167180
Thread now closed or I would have continued my Thread there...

I am currently trying to get the identical record player Steepletone 5002D working - I haven't posted any photos - those in aforementioned Post are the same as mine (albeit AlanMK71's had a dodgy fuse!).
Everything seems in order and with a reasonable stylus (perhaps the original) installed I can hear the sonic reproduction direct from the stylus (at a low volume of course!)

Alas I have not got the correct speakers!

The rear of unit has three x 5-pin female connectors.

One is labeled 'stereo' and I assume is a speaker? DIN connection point which is wired to the Main PCB and uses all 5 pins, with Pins 1 & 3 BRIDGED as a pair at rear of connector, and Pins 4 & 5 BRIDGED also as a pair at rear of connector.
Pin2 Ground is also BRIDGED to DIN outer casing Shield.
Both feeds from Main PCB to Pins1/3 and Pins4/5 are resistored by gold/yellow/blue/green banded resistor.
This looked a little complicated so I have not tried using this as a speaker output.

The other two DINS, I guess by their labeling, are 'Left 8 Ohm' and 'Right 8 Ohm' channels. Perhaps these are mono channels, as: -
Pin1 LHS is wired to Pin1 RHS,
Pin2 LHS is wired to Pin2 RHS,
Pin3 LHS is wired to Pin3 RHS,
Pins 4 & 5 have no connection.

I noted Member Ben's comment "edit: just seen post 6, which confirms what I mentioned earlier. Just don't try connecting other speakers to it!"

I therefore held back from wiring up a standard set of 8 Ohm speakers for fear of damaging them - potentially a risk if the light feed to the original speakers causes standard speakers to blow.

I have checked the voltages (relative to Pin2 Ground): -
Pin1's = 16v DC
Pin3's = 0.02v DC (on occasion)
Altering the volume slider controls made no alteration to voltage measured.

As a test, I could try some 8 ohm 10W speakers from a broken TV, but thought I would ask if anyone would know the right way to wire up such a speaker set up, in case I damage the Steepletone unit, as well as the speakers? I would have thought using Pin1's is a no-no at 16V

Last edited by AnGSB8s; 23rd Feb 2021 at 1:36 pm. Reason: typo
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Old 23rd Feb 2021, 3:32 pm   #2
Edward Huggins
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Default Re: Steepletone 5002D Speaker Wiring

The 5 pin DIN marked "Stereo" is not for speakers, but for recording and playback from a tape recorder. It's exteremely unusual to see 5 Pin DIN sockets ever used for speakers and I expect the other spare pins are used to connect the flashing lights arrangement and these may carry higher voltages. Double check the actual speaker LH- LH+, RH- RH+ pins on the rear of these sockets with a continuity tester before you hook up any standard 8 ohm speakers i.e. 2 wires to each speaker.
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Old 24th Feb 2021, 12:37 am   #3
AnGSB8s
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Default Re: Steepletone 5002D Speaker Wiring

@Edward Huggins
Thanks for your reply! Thanks for ruling out the stereo DIN for me!

Re-reading my post, I see I made a copy / paste error in my initial Post, so details on Pin1's on LHS & RHS DIN connectors was totally wrong:-

Quote:
The other two DINS, I guess by their labeling, are 'Left 8 Ohm' and 'Right 8 Ohm' channels. Perhaps these are mono channels, as: -
Pin1 LHS is wired to Pin1 RHS,
Pin2 LHS is wired to Pin2 RHS,
Pin3 LHS is wired to Pin3 RHS,
Pins 4 & 5 have no connection.

I have checked the voltages (relative to Pin2 Ground): -
Pin1's = 16v DC
Pin3's = 0.02v DC (on occasion)
Altering the volume slider controls made no alteration to voltage measured.

It should have read: -

Pin1 LHS DIN is fed by an individual Blue wire from Main PCB
Pin1 RHS DIN is fed by an individual Red wire from Main PCB
(Pin1 LHS is NOT wired to Pin1 RHS)
Pin2 LHS is wired to Pin2 RHS,
Pin3 LHS is wired to Pin3 RHS,
Pins 4 & 5 have no connection.

Pin3's = 16v DC
Pin1's = 0.02v DC (on occasion)
Altering the volume slider controls made no alteration to voltage measured.


Not that this helps me in anyway, as I knew this before I posted.
Perhaps I should re-post as I made such a hash of the initial post.
Teach me not to do things when tired.
But corrected info vital to anyone kind enough to be making some checks for me.

I think I will proceed with caution and try: -
LHS DIN Pin1 and Pin2 to LHS Speaker
RHS DIN Pin1 and Pin2 to RHS Speaker

Whether 16v (measured without any load) on Pin3 is acceptable to drive a speaker I have no idea, but could be the speaker light power feed?
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Old 24th Feb 2021, 11:09 am   #4
Edward Huggins
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Default Re: Steepletone 5002D Speaker Wiring

It is most likely to be the speaker light power feed. Do not apply any measurable voltage to your speakers over 1.5V - if at all.
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Old 24th Feb 2021, 3:46 pm   #5
simpsons
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Default Re: Steepletone 5002D Speaker Wiring

I wonder if the clue to your conundrum is the audio output chip?

Check out the IC type number and in looking up the preferred circuit, trace back the loudspeaker out to the loudspeaker DIN socket.

As mentioned, the unusual "Disco" lights voltage should not go anywhere near the voice coil.

Good luck

Chris
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Old 25th Feb 2021, 4:37 am   #6
AnGSB8s
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Default Re: Steepletone 5002D Speaker Wiring

@Edward Huggins
I went back to your idea of measuring continuity on LH & RH Channel DIN connectors: -

Quote:
Originally Posted by Edward Huggins View Post
The 5 pin DIN marked "Stereo" is not for speakers, but for recording and playback from a tape recorder. It's exteremely unusual to see 5 Pin DIN sockets ever used for speakers and I expect the other spare pins are used to connect the flashing lights arrangement and these may carry higher voltages. Double check the actual speaker LH- LH+, RH- RH+ pins on the rear of these sockets with a continuity tester before you hook up any standard 8 ohm speakers i.e. 2 wires to each speaker.
I don't have a digital tester, I try to get by with an old-school analogue meter. But this should be adequate for this task....
But I don't really know what resistance to expect, or what I would learn from doing continuity checks?

I performed the following steps:
1) Powered up record player, with vinyl playing
2) Set my meter to Resistance x 1000 range
3) Measured resistance across Pins 1 & 2 on LH channel (Pin 1 being the one where I previously measured very little or no voltage, Pin2 clearly is ground from PCB)
4) Resistance reads 14 Ohms
5) Repeating process for Pins 1 & 2 on RH channel also gives 14 Ohms
6) Either Channel - 14 Ohm increases to 30 Ohms when record stops playing
7) Resistance between Pin 1 LH with Pin 1 RH reads 65 Ohms, although this increases to circa 500 Ohms if the record stops playing
8) As expected Pin 2 LH with Pin 2 RH measure zero Resistance (both wired together and go to ground)

On this basis, and noting both your (and Chris's) advice to avoid the higher voltage Pin3's, I wired a pair of 10W 8 Ohm TV speakers temporarily to the Deck (LH Pin1 to LH+ speaker input, LH Pin2 to LH- speaker input, RH Pin1 to RH+ speaker input and RH Pin2 to RH- speaker input).

No luck, no sound from speakers.

So perhaps there is a Main PCB fault somewhere...
Or the 16v Pin3s are used as + feed to speakers in some way, but use
resistor? circuitry inside the speaker box to downsize the voltage to a sensible level for speakers.

I'll try taking Main PCB out to inspect its upperside for any damage - but suspect I will need to schematics to solve this one.....
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