Sony TC-95A Quiet Line Out

[alfabarry]

Update for anyone who's interested: I have now obtained a jack to DIN lead that delivers perfect performance from the TC95A to the ITTs: it differs from the others in being mono only and of "new old" vintage origin... possibly, given the spec, packaging, and plastics, dating from the 1970s.

The packaging helpfully includes the attached schematic, indicating that pins 3 and 5 are connected. In any event it delivers ample volume and excellent quality

While this does not solve the mystery of the differing results with modern DIN leads and as compared to the TC-95, my central interest here - in recreating an TC-95A to ITT radio combo from 1973/4 - is addressed in full period fashion. I am happy. "Very happy" would require a period Sony VM-0124 three pin power lead....

[TonyDuell]

Can you describe the leads that don't work? Do they have stereo (3 contact) jack plugs on them?

The 3 contact plug effectively divides the sleeve (earth contact) of the mono plug into a shorter sleeve (still earth) and the ring (right hand channel). The tip is much the same between the mono and stereo plugs.

Mono sockets can make contact with the sleeve anywhere along its length. Such a socket might therefore connect to the ring of a stereo plug or to both ring and sleeve. This could end up with no earth, or with the signal shorted out. Either could give quiet or no signal.

[alfabarry]

Originally Posted by TonyDuell

Can you describe the leads that don't work? Do they have stereo (3 contact) jack plugs on them?

The other leads are all fitted with stereo jacks (well I assume they are as they have two black rings as opposed to one on this vintage lead). Herewith image of the vintage plug (R) alongside a modern plug (L) from one of the other modern jack-to-DIN leads (which all look alike).

What you say sounds very plausible. The delivery via the vintage plug is full throated in a way that even the best of the others is unable to match.... Of course if I connect these leads to a TC95 rather than the TC95A, they all perform perfectly well, with the vintage lead offering no advantage..

The biggest difference in spec between the older 95 and the later 95A is that the latter is earthed, using the elusive 3 pin VM-0124 lead whereas the former is not earthed and uses a four pin socket to accommodate either 6volt or AC feeds via the appropriate four pin power cord (I actually have one of these). The 95A also boasts an ac on/off switch, separate single pin DC input and an end of tape shutoff, but otherwise they appear almost identical.

[Mooly]

Really pleased to hear that you have found a solution that works

The mystery leads and set up would need more detailed testing to see why they don't work as expected... but I'm pleased you have got a result.

[alfabarry]

Thanks Mooly. I would never have focused on the leads (rather than the player) as solution in the first place without this thread and the helpful comments offered.