ATR-60-16 recording problem

[Arne Wachtmann]

Hi,
I've a problem with a Tascam ATR 60-16.
Playback works fine on sync and repro head.
Input levels are the same on every channel. But when recording I get almost no signal (around -25dB) to the tape on tracks 1-11. The other tracks work fine. I reseated all the cards, cleaned all plugs, adjusted the bias level, bias trap and erase bias tuning. Can't get any higher levels (accept für the 7dB the bias is set under max). Swapped cards with working channels, no difference, 12-16 work fine, the others don't. Played around with head contact and azimuth. No luck either. I measured the resistance of the sync head coils, all 30 Ohm consistent.
I've measured the signal that's going to the sync head on the motherboard for Track 9 and 16 (P061 and P068) they look identical to me. (1kHz at 0dBVU resolution: 10V/dev and 1ms/dev)

I'm running out of ideas...

 

[Laszlo]

Hey Arne,
i am not an expert of this machine, especially not of the multichannel machines, just saw that noone picked up the topic, which can be frustrating for a newbie like me, hence my response.
There are fine experts of this on this forum as well, why dont you try Skywavebe (Sam) or Alex Nikitin in a PM.
My opinion as an electric engineer is that this should be rather a sytemic issue since it happens in a bigger group of the channels. I would look for either a damage on the mother board, or some issue with the control panels portion that is reponsible of switching the Rec and Repro sound paths..It is difficult to tell anything without seeing the schematics though.
Please let us know how you progress, good luck,
Laszlo

 

[SkywaveTDR]

Maybe the ideas are not forthcoming as there is little info to work from. What does the head surface look like?

 

[Arne Wachtmann]

Hi, thanks for your answers. The heads are worn, but I can see no gaps or damages. I‘ll post a picture as soon as I get back to the machine.

 

[Arne Wachtmann]

So I finally got to make some pictures of the sync and repro heads. It's not so easy to get them without reflections...