Really Obscure Retro Tech Question - Grundig Stenorette

JP08

I've got a minor reputation in the family for being able to "fix things". Hence every now and then get given old kit / problems to fix / solve.

So far it's been mainly old radios / clocks etc - but this time Brother-In-Law has passed on a bit of a doozy this time (along with another clock !) - to get recordings made on Grundig Stenorette cassettes of stories his father recorded when B-I-L was a child onto a PC.

He's kindly(!) supplied two Stenorettes (one working - one not), various accessories (headset and footswitch, microphone / speaker / control handset unit) and a box of a dozen or more cassettes.

Some links so you can see what I'm on about.
Stenorette (working one) - https://commons.wikimedia.org/wiki/File:Grundig_Stenorette_L_o.jpg
Cassette - https://commons.wikimedia.org/wiki/File:Grundig_Stenorette_SL_Cassette_30.jpg
Microphone - https://commons.wikimedia.org/wiki/File:Grundig_Mikrofon_GDM750_f%C3%BCr_Stenorette.jpg
Headset (also piccy of non working Stenorette) - http://www.museumoflondonprints.com/image/134467/grundig-ltd-grundig-stenorette-dictaphone-20th-century

I've also managed to find a partial circuit diagram : http://www.vintage-radio.net/forum/attachment.php?attachmentid=20069&d=1222086291

So - several questions.

1) Anyone got a better circuit diagram ?

2) The motor in the working machine is a bit weak - struggles to rewind cassettes. I've tried lubing every bearing in sight, and dismantled / cleaned / reassembled the rewind shaft as far as I can (not very) which has helped, but any more ideas ?
The rewind wheel still feels somewhat resistant to turning. This looks like it has been a problem in the past as the wheel has been resurfaced in what looks like old Elastoplast to give a little more friction.

3) The output sound quality is abysmally noisy, any recommendations for free software to clean up the results (this any good ? http://www.audacityteam.org/)

4) I've figured out how to bypass the footswitch (shorting out pins 2 and 3 on the footswitch socket - not doing this means the machine won't playback), and the output to the headset speaker is pins A and B on the mic / control socket (took the connector apart on the headset !). Any reason why I shouldn't solder a lead with a phono plug on the other end across those pins and use this to feed the mic socket on the PC ?

5) Some of the cassettes appear to be a little stiff to turn too. I'm old enough to know about the pencil trick with standard audio cassettes - any tricks to suggest for these beasties ?

6) What to do with all the kit once/if transfer has been successful (other than dumping - I hate to throw old old kit) ?

I thought about recommending going down the professional transfer route - a quick google found these guys - http://www.audiorestored.com/transfers/cassette-transfer/grundig-stenorette - but at £25 a cassette brother-in-law would be looking at £300+ !!!

Fightsback

Have you tried asking on the forum here as they will have much better specialist knowledge and may help in sourcing any parts you require:

http://www.radiomuseum.org/dsp_forum_folder.cfm?folder_id=1

Audacity has noise reduction and you can adjust the level so it's not too harsh resulting in artefacts but as you're looking in the vocal range only it shouldn't be that much of a problem.

Note the audacity download website did have a breach and there was some nasty malware embedded but this has be contained and corrected.

http://www.zdnet.com/article/fosshub-serves-up-mbr-compromising-versions-of-audacity-and-classic-shell/

Owain_Moneysaver

The headset output is likely to overload the mic socket and you would be better to use a line-in socket if you have one. You might need an isolating transformer to prevent earth loops.
https://www.amazon.co.uk/dp/B000NVWB9O/

JP08

Fightsback - thanks for the link (and the ZDNet one - seen the story in The Register, but didn't make the mental link last night when searching for software). Found it a little German centric, but pointed me in a suitable direction and now asking with these guys : http://www.vintage-radio.net/

Owain - thanks, will have a good look round the PCs tonight to see what's available in terms of sockets.

googler

There may be some mileage in acquiring a proper tape recorder, which has working mechanics, take the tape out of the cassette, load it onto open reels, and play it back on that, rather than the Stenorette.

You'd need to match the machine to the width of tape and track configuration, which is what I can't find from searching.

JP08

Googler - 1/4 inch tape, and 1 track I think (from looking at the mechanism, single recording head definitely, mono recording definitely, and no means of flipping "sides") ...

googler

JP08 wrote: »

Googler - 1/4 inch tape, and 1 track I think (from looking at the mechanism, single recording head definitely, mono recording definitely, and no means of flipping "sides") ...

Any quarter-inch 2-track machine will read 90% or so of the tape width, and a 4-track machine about half, and unless my schoolboy physics is misleading me, I think you should get a usable result from that.

Gets around the problems with the mechanics, gets around the problems with tape sticking in the cassettes ... if you get a machine with decent working electronics, etc. ...

Have you determined if it ran at a standard tape speed? 15/16th, 1 7/8th, 3.75 etc?