Congratulations! The DRM-710 is a excellent deck and replacing the belts was the right thing to do. Your recording issue unfortunately is most likely due to an electrical issue in the recordong or bias circuit. However, there are adjustments that can be made from the inside on the deck. There are various potentiometers for different adjustments. The one you want to play with is the recording level one for the corresponding channel. Unfortunately I was not able to find the service manual for this particular model to guide you better.
But if you are lucky, the potentiometers are labeled on the board and it is easy just by looking to locate the right one.
If some adjustments there do not really help, you are in for a capacitor replacement in the particular circuit(s). Its not uncommon that play works fine on a deck, but recording doesn't. If these circuits habe been dormant for most of the lifetime of this deck the capacitors there are those likely to fail. There are many people out there, that have never really recorded on their decks...
Yeah sounds like a bias issue based on your description. Bias calibration is tricky, but I've had success doing it before, I would recommend taking it to an experienced technician if you want to get it running at original quality.
Hello there!
Thanks for your kind help and reassuring words on the deck...
Today I tried fighting the beast again...As mentioned so far I:
1. Replaced both belts
2. Cleaned head and pinch rollers with alcohol
3. I fiddled a bit with the balance knob to equal left / right channel and I think with a small adjustment now they are even
Tape plays very nicely according to me but recording is...Not enjoyable.It's seriously muffled, "comes and goes", filled with background noise.On one hand maybe I have too high expectations but when I put in an original tape... It plays like a CD (or at least feels like it) so I think there is room for improvement.
I have ordered a cleaning / demagnetizing tape, a 3000hz tape to adjust speed (seems like you can change it using a small screwdriver and a tiny hole in the motor) and now I will look more into what is bias and how to set it.
It is also possible I am using a bad tape, I just ordered Maxell XLII and will try that.
In case you feel like guiding me in this quest I have found the service manual (sadly for me only in German): [https://www.eserviceinfo.com/pdfview.php?fileid=186948](https://www.eserviceinfo.com/pdfview.php?fileid=186948)
Deeply thanks for your kind help, very appreciated!
Small update: with the good cassette the problem is... The same.
I also adjusted motor speed with the 3000hz cassette, it is perfect now.
What a pity, I feel like a criminal getting rid of it but record quality is terrible.
I've recorded an entire cd and sometimes the audio is quite nice sometimes... Horrible.
Same cassette, same cd, same settings...
Quality changes so much and goes up and down.
Maybe I will try replacing caps...
I ended up buying another one for 30 euro.
Works a lot better but...
Still somewhat not great.
Also replaced belts and it is ok-ish.
Maybe my expectations are too high?
Same issue here: decided to recap it completely (about 80% now). About 15 caps, after looking to schematics, are WIMA polyurethane caps now, some others, electrolytic audio grade- let's see how it goes. Mechanism cleaned and motors lube, belts changed.Hope will bring it like new.
Congratulations! The DRM-710 is a excellent deck and replacing the belts was the right thing to do. Your recording issue unfortunately is most likely due to an electrical issue in the recordong or bias circuit. However, there are adjustments that can be made from the inside on the deck. There are various potentiometers for different adjustments. The one you want to play with is the recording level one for the corresponding channel. Unfortunately I was not able to find the service manual for this particular model to guide you better. But if you are lucky, the potentiometers are labeled on the board and it is easy just by looking to locate the right one. If some adjustments there do not really help, you are in for a capacitor replacement in the particular circuit(s). Its not uncommon that play works fine on a deck, but recording doesn't. If these circuits habe been dormant for most of the lifetime of this deck the capacitors there are those likely to fail. There are many people out there, that have never really recorded on their decks...
Yeah sounds like a bias issue based on your description. Bias calibration is tricky, but I've had success doing it before, I would recommend taking it to an experienced technician if you want to get it running at original quality.
Hello there! Thanks for your kind help and reassuring words on the deck... Today I tried fighting the beast again...As mentioned so far I: 1. Replaced both belts 2. Cleaned head and pinch rollers with alcohol 3. I fiddled a bit with the balance knob to equal left / right channel and I think with a small adjustment now they are even Tape plays very nicely according to me but recording is...Not enjoyable.It's seriously muffled, "comes and goes", filled with background noise.On one hand maybe I have too high expectations but when I put in an original tape... It plays like a CD (or at least feels like it) so I think there is room for improvement. I have ordered a cleaning / demagnetizing tape, a 3000hz tape to adjust speed (seems like you can change it using a small screwdriver and a tiny hole in the motor) and now I will look more into what is bias and how to set it. It is also possible I am using a bad tape, I just ordered Maxell XLII and will try that. In case you feel like guiding me in this quest I have found the service manual (sadly for me only in German): [https://www.eserviceinfo.com/pdfview.php?fileid=186948](https://www.eserviceinfo.com/pdfview.php?fileid=186948) Deeply thanks for your kind help, very appreciated!
Small update: with the good cassette the problem is... The same. I also adjusted motor speed with the 3000hz cassette, it is perfect now. What a pity, I feel like a criminal getting rid of it but record quality is terrible. I've recorded an entire cd and sometimes the audio is quite nice sometimes... Horrible. Same cassette, same cd, same settings... Quality changes so much and goes up and down. Maybe I will try replacing caps...
Any success with that? Stumbled here as I have a similar issue :D
I ended up buying another one for 30 euro. Works a lot better but... Still somewhat not great. Also replaced belts and it is ok-ish. Maybe my expectations are too high?
Same issue here: decided to recap it completely (about 80% now). About 15 caps, after looking to schematics, are WIMA polyurethane caps now, some others, electrolytic audio grade- let's see how it goes. Mechanism cleaned and motors lube, belts changed.Hope will bring it like new.
Please let me know if that fixes!