Hello! I just recived as a gift from a friend of mine this old tape deck. It dates to about 1977 I think, and it's a beautiful model in minty condition (little used) that I believe shlould be worth the effort to use in my system (I never had a tape deck). Where should I start to make it like new? Changing capacitors, transistors, things like this. And what about the mechanics?
Hello again! I tried the tape deck after cleaning it. I cleaned the heads with normal alcool, and the sound I'm getting is very boomy, distorted and with no high-frequency content (it has nothing over 1kHz)... What should I do? The other mechanics are working well, maybe I just have to replace some capacitors (?) to extend the frequency range... I've even turned off dolby NR, but with little results.
Yes, this is happening with tapes that I've prerecorded on my JVC mini-hi-fi, and on that they play well. On the Technics they play so bad. How can I adjust the allignment? Others suggested me of tweaking the azimuth (don't know what is) and demagnetize the head. Or just replace it. What shall I do?
Ciao Giaime,
to adjust the alignment (or azimuth) of the head, you have to adjust a small screw which is usually placed next to the head itself. This screw helps you adjust the relative skew between head and tape.
To de-magnetise the head, there are some special devices around (TDK was manufacturing a de-magnetiser in the shape of a cassette, you just have to insert it into the deck and press play for a couple of seconds).
Cheers,
Bruno
to adjust the alignment (or azimuth) of the head, you have to adjust a small screw which is usually placed next to the head itself. This screw helps you adjust the relative skew between head and tape.
To de-magnetise the head, there are some special devices around (TDK was manufacturing a de-magnetiser in the shape of a cassette, you just have to insert it into the deck and press play for a couple of seconds).
Cheers,
Bruno
Ok... don't know how I did it, but now the oscillation is gone... but before I cleaned the switch, the resistance across it was 0.3 ohms, after it measured the same. Anyway, problem solved... What can I do for that big loss of highs? Btw what I hear is wonderful, more "stereo" and involving than my JVC. I think this deck has great possibilities but it doesn't have any hi-end. I'm not using the best cable possible, but I doubt it's this causing the problem...
And what are all those trimpots inside it doing? I can't find a schematic of it...
I see that the outputs are transformer coupled (yes, there are 2 small transformers on the board, about 1 cm tall and 1x1cm. Is this usual in tape recorders?
Do I have to change the many electrolytics I see in the signal path for film caps? Will this improve the situation?
And what are all those trimpots inside it doing? I can't find a schematic of it...
I see that the outputs are transformer coupled (yes, there are 2 small transformers on the board, about 1 cm tall and 1x1cm. Is this usual in tape recorders?
Do I have to change the many electrolytics I see in the signal path for film caps? Will this improve the situation?
Don’t start fiddling with the trimpots inside unless you have a detailed manual.
The loss of highs is most probably what Al and Bruno said.
If possible, try recording a 3Khz or so signal on the JVC.
Play it back on the Technics and align the playback head. While doing so, listen with a headphone for best reproduction or measure the output of the deck with a scope and align for highest amplitude.
/Hugo
The loss of highs is most probably what Al and Bruno said.
If possible, try recording a 3Khz or so signal on the JVC.
Play it back on the Technics and align the playback head. While doing so, listen with a headphone for best reproduction or measure the output of the deck with a scope and align for highest amplitude.
/Hugo
I can't find any manual for that, neither a schematic...
I would do so, but...
1) there isn't any adjust screw; I mean the head is fixed by 2 screws on a piece of plastic that moves when I push play
2) the JVC has the record side broken
I can only play with it, it does record but difficultly (a mechanic problem) and it does record only right channel...
Anyway I've changed the head with a new one: see results here (sorry, these two threads are running in parallel on the same subject, that wasn't my fault. Sorry again)
http://www.diyaudio.com/forums/showthread.php?s=&threadid=53761&pagenumber=2
I would do so, but...
1) there isn't any adjust screw; I mean the head is fixed by 2 screws on a piece of plastic that moves when I push play
2) the JVC has the record side broken
I can only play with it, it does record but difficultly (a mechanic problem) and it does record only right channel...Anyway I've changed the head with a new one: see results here (sorry, these two threads are running in parallel on the same subject, that wasn't my fault. Sorry again)
http://www.diyaudio.com/forums/showthread.php?s=&threadid=53761&pagenumber=2
News! News! News!
Oh hello to everybody. Obviusly the head I'm talking about in my previous post is a double sided one, for autoreverse decks. Not my case.
I found a suitable head, and I mounted it. I tweaked its position with the screws, to search the sonic nirvana. I found it completely eliminating the left screw, letting the head float on that side about 1 mm over the plastic base.
But now the deck is oscillating another time! I've checked all the wires, the solder connections, cleaned the pots, the contacts... someties sound doesn't come out and the VU meters have no singal, sometimes they go to the max (oscillation occurring), sometimes strange noises, sometimes the position of a particular trimpot (the one that seems to control the left channel volume, but also its tone - when the volume gets lower, the tone gets muffled)...
Just don't know what more to do...
Oh hello to everybody. Obviusly the head I'm talking about in my previous post is a double sided one, for autoreverse decks. Not my case.
I found a suitable head, and I mounted it. I tweaked its position with the screws, to search the sonic nirvana. I found it completely eliminating the left screw, letting the head float on that side about 1 mm over the plastic base.
But now the deck is oscillating another time! I've checked all the wires, the solder connections, cleaned the pots, the contacts... someties sound doesn't come out and the VU meters have no singal, sometimes they go to the max (oscillation occurring), sometimes strange noises, sometimes the position of a particular trimpot (the one that seems to control the left channel volume, but also its tone - when the volume gets lower, the tone gets muffled)...
Just don't know what more to do...
Hello! I still have that oscillation problem. When I do like a fellow here suggested (press record with the pause on) I notice a momentary jump of the meters and a slight dim of the tape deck lights. What can I do?
I've recognized most of the trimpots in the unit just judging by the ear. I've cleaned them but still no solution for that oscillation. I cannot turn up the volume trimpot over -20dB because it would start oscillating. What to do?
I've recognized most of the trimpots in the unit just judging by the ear. I've cleaned them but still no solution for that oscillation. I cannot turn up the volume trimpot over -20dB because it would start oscillating. What to do?
Hi I have Technics RS-615US. It doesn't work properly and I must fix it. Somebody had been trying to recover it, but he didn't managed. Now i must exchange capacitors and regulate it. As I see somebody had been regulating resistors, but I think that he didn't it correctly. I must do it correctly and I need Service Manual or at least schematic.
Thanks for help.
Thanks for help.
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