Beocord 8004 recording issues

greetings All,

while waiting till chinese ’new year celebrations’ are finally over to get parts for the BM I decided to give my BC a service, replacing belts and rubber tyres (thanks Martin) when I noticed the it stopped recording ?!!

now, usually I only play tapes but the other day was something really interesting on the FM....put a blank tape in, activated ‘record on’, pressed ‘record’ but not sign of anything on the PPM nor any audio on the tape 😡

what am I missing here ? Sitting on my brain or is there indeed an issue with the record-function ??

help or pointers as always are most welcome - don’t be shy 🙄😁🙏

ALF

Thanks Martin

for pointing out that switch at the lower front.....never noticed that one as most times only replay of tapes is used and that worked at all times !

what I noticed though there is an extra cable fitted, coming out from the side with a sticker on

“remote switch only” ?

I now begin to wonder if that is part or cause of the recording issue ?

again, as usually only replay is used and working there was no attention drwan to that cable.....

I will investigate and report back

ALF

 

Ok,

the switch at the lower front is set correctly, the added cable turned out to be not original and was fitted to the keyboard operating

a kind of remote control - I removed it, it had no impact in to the issue at hand.

I noticed the MPX switch had been removed and there are jumpers in placed - looks it had been bridged ?!

well, there is still no audio signal coming from a selected source when Record is activated ?

‘Rec open’ lights up, Record is flashing....but no flicker on those PPM ?

further investigation is on tomorrow.

any pointers or suggestions ??? 

ALF

I am waiting for a decent full-size circuit diagram - just wondering whether the BC8002 circuit would be a good start, as it only differs from

the BC8004 by not having Dolby C included ?!

it doesn’t look like a connection problem after close examination, so......is there a permanent ‘Record Mute’ possible preventing any incoming signal

from being recorded or.....is there any source signal coming in at all ?

the switch next to the Amplifier DIN plug is “missing”  or provisions for such a switch had been made to incorporate that one at a later series, adressing sensitivity issues between DIN and Cinch connection .....so, that’s not it either.....!

if you guys can think of othets reasons please let me know 🙏

ALF

Is it fair to assume not many Beocord users are left among us anymore ?!😳

turning to the Beocord 8004 SM:

what I can not find are exact definitions on various testpoints.....what are you supposed to measure ?

i noticed in other SMs there are defined voltages one should measure but nothing here unless blindness came over me ?!

for example TP7 and TP8 on board 2 ??

so far no adverse findings why the recording function isn’t working ?

the PPM works fine in PB mode, flickering up and down but nothing to see when record is activated, no matter how high the rec sliders are set!

15V and -15V at the PPM rectifier are present,

however the test conditions at TP7/8 (rec amplifier) are not clear ?!

perhaps that is a starting point ?

anyone, any light on this ?

ALF

ALF,

You’re clearly more technically capable than me, so I’m sorry to suggest something really basic: are you certain that the DIN cable you’re using to connect the BC8004 to the amp is fully wired? That is, is it carrying sound both ways: from BC to amp and vice versa?

And is your amp output to the TAPE socket working?

Lawrence

Hi Lawrence,

no need to be sorry....no issue ever is too simple or basic !

thank you for your genius reply - one should never assume.

I have gone almost through the comlete circuit diagram, verifying basically all voltages mentioned...

no adverse findings 😳😬

The last thing I suspected would have been the inter-connect, using a 7-pin DiN cable from Steve (sounds heavenly)

without any issues during Playback !! So, the suspicion was there: someth8ng is wrong in the deck with the Rec Function ?!

using an old 5-pin DIN cable after your reply.....and oh wonder: the PPM flickers and Rec Function is working ?!?!

meaning the brand new 7-Pin DIN cable has to have a different wiring !

at last something to work on - once again: thank you so much for that most important pointer, simply brilliant 🤙🤗

now back to sort out the wiring task ahead 😬

ALF

Just spotted your comment section re Beocord 8004. One of your helpers mentioned that there is not many of us left. Yes, cassettes are very low on the useful scale, but they tell me in the US they are trying to make a return. I worked for B&o for nearly 40 years and are similar to Steve making many cables for my customers around Australia, NZ and the world.

Nice to hear you are all good with your wiring up. It is possible that the lead from Steve was made as a one way lead. The Cass deck has a 7 pi connection. The pins have a common earth, middle pin and for the other two pins either side of center are for L+R input and L+R output. A five pin will fit into a 7 Pin Din and if not forced in the wrong way will work fine. The 2 added pins are for data transfer. Pins 6 & 7 are to talk to another B&o amplifier with datalink. The B&o amplifier operates the cassette deck from the amp via the extra two pins.  

Just a tip: While recording, if the input level is either too high or too sold you will find adjustments underneath the BE8004 and a switch makes "Line-Din". Getting this correct will change the quality of your recording.

Another tip: if you plan to play back you tape recording on another machine you might find making the recording using Dolby B is better than using Dolby C, as C may not compatible with other Dolby C and cause a breathing affect. The Beocord 9000 is 100% a hybrid using the Dolby C.

Tip: If for some reason that the record level drops out on one Channel, Quickly start and stop recording, this may free up the internal switch.

 

All the best from South Australia

Regards

Greg Ferres

Digital Perception 

Thanks Greg,

indeed it is a one-way cable I used, originally assigned for a Beogram - Beomaster connection.

just received a response from Steve clarifying exactly what you suspected.

I certainly wasn’t aware of the fact.....one never stops gathering experience.

thank you anyway - nice of you to respond.

ALF

Hi ALF,

Sorry, I just saw this thread.  Yes, the cable that we discussed on email was for a Beogram turntable, so this just has the playback pins wired (plus the extra grounding for the Beogram).  This will work for playback of cassettes from the Beocord, but it won't let you record onto cassettes.

This cable will give you recording and playback, plus remote control of the Beocord via Datalink:-

https://soundsheavenly.com/tv-masterlink-control-and-sync/15-259-datalink-cable-for-bo-beocord-etc.html#/4-length-3m

Please ask if you need any further help.

Kind regards, Steve.