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johncool
06-09-2009, 11:35 AM
Hello all!

I never thought posting on the cassettes forum, but last Sunday I dug out my recorder from the closet, because I have a need to record cassettes once again. One of my friends has a cassette player on his car and he didn't have any tapes so... cassette tape revival! *Hi5*

Anyway, I cleaned it throughly: insides, deoxit all the switches, checked the belt which (amazingly) was ok and the tape path (heads are still ok). But it's off calibration when it comes to recording. I still have a bunch of unsealed tapes and I tried one TDK-SA... the results were awful. Even by messing around the bias potentiometer I never managed to get the same results like those I have on other tapes I have recorded with it and those still play great.

Mind you... this Denon is just a modest entry model. No dual capstan, 3 heads or all that stuff that's making me think in buying a cassette recorder again *wink* But I'd like to bring it up to spec. Does anyone knows where can I find a service manual for it (free if possible)?
A.N.T.
06-09-2009, 11:57 AM
I still have a bunch of unsealed tapes and I tried one TDK-SA... the results were awful. Even by messing around the bias potentiometer I never managed to get the same results like those I have on other tapes I have recorded with it and those still play great.

One more thing to check - if the deck correctly recognises the cassette type.

Alex
Scorpion8
06-09-2009, 12:55 PM
Does anyone knows where can I find a service manual for it (free if possible)?

I may have one, as I was into Denon decks for quite awhile and still own 4 of them. If not I may send you what I have as many of their PCB's use the same layout and general tune-up procedures.
johncool
06-09-2009, 01:08 PM
I may have one, as I was into Denon decks for quite awhile and still own 4 of them. If not I may send you what I have as many of their PCB's use the same layout and general tune-up procedures.

That would be an awesome help. Thank you so much! :)

One more thing to check - if the deck correctly recognises the cassette type.

My Denon does that (it's not a sensor... it's more of a mechanical gadget that checks the number of holes present in the top of the cassette shelf, hence recognizing its type).

Oh... one more thing: when I said that I messed around with the Bias, I meant the Bias Fine control on the front of the machine NOT on the one that's present on the PCB (I'll need the SM before doing such thing by myself).
Scorpion8
06-09-2009, 04:17 PM
My Denon does that (it's not a sensor... it's more of a mechanical gadget that checks the number of holes present in the top of the cassette shelf, hence recognizing its type).

That mechanical gadget connects to two (or more) leaf switches that determine Type I, II or IV tapes by sensing which leaf switches are tripped and which are not. They trip when they fall into the tape selector holes, otherwise they stay up and short to provide a signal back to the deck's logic controller.
Scorpion8
06-09-2009, 10:00 PM
The closest I come is a DRM-540 Service Manual in German. Emo-Fan was supposed to get it translated for me as a special project for some of his female German students at the high school that he wanted to tap but I guess it didn't happen .....*grin*
johncool
06-10-2009, 04:56 AM
The closest I come is a DRM-540 Service Manual in German. Emo-Fan was supposed to get it translated for me as a special project for some of his female German students at the high school that he wanted to tap but I guess it didn't happen .....*grin*

*lmao* one can't always win...

Thanks about your explanation on the leaf switches. I knew how it worked, but I lacked the vocabulary to explain... my English is not good enough.

About your service manual I guess it'll have to do, although I studied German for 3 years my knowledge of the language is terrible nowadays (it was 12 years ago). So if you can send it to me... I'll give it a shot. *cool*
Scorpion8
06-10-2009, 08:15 AM
So if you can send it to me... I'll give it a shot. *cool*

Sure. PM me an e-mail address that will accept large files and I'll send it out tonight. Otherwise I can upload it to YouSendit to download at your leisure.... still need the e-mail address though.
johncool
06-10-2009, 08:28 AM
Sure. PM me an e-mail address that will accept large files and I'll send it out tonight. Otherwise I can upload it to YouSendit to download at your leisure.... still need the e-mail address though.

PM sent! My mail address accepts large files without a problem.

Thank you for your help! *Hi5*
Scorpion8
06-10-2009, 05:34 PM
Sent today to your e-mail address.
johncool
06-12-2009, 05:23 AM
Thanks! I've given it a quick look and I can guide myself through it.

Tomorrow I'll try to get this machine under spec... or close enough. I'll post here the results soon.

Once again thanks for all the help and advice *thumbsup*
johncool
06-16-2009, 08:23 AM
An update: It's now singing as it used to.


Thanks for all the help! *Hi5*
Scorpion8
06-16-2009, 10:37 AM
An update: It's now singing as it used to.

What did you do to it?
Capricorn
08-20-2011, 01:02 PM
The closest I come is a DRM-540 Service Manual in German. Emo-Fan was supposed to get it translated for me as a special project for some of his female German students at the high school that he wanted to tap but I guess it didn't happen .....*grin*

I am having trouble with a DRM-540 and I could really use a service manual. If it has the schematics in it, I'd love to have it. If you still have a copy, could you please send it to me, this is my main cassette workhorse, I have to get it fixed! Thank you!