The Workbench

Re: Beocord 3500 (1988) vu meter

pepps — Mon, 30 May 2011 13:36:38 GMT

Final update!!

Dear all - problems finally over! I remembered a long while ago now sajpratty kindly donated me a Beocord to help with wow and flutter problems I was having initially. So I dug this out of storage and swapped out my tape mechanism into his old deck. Swapped my inner tray (mine has the B&O HX-Pro logo, rather than the standard one Dolby use) and my lid too. Works a treat!

I get proper levels now, bouncing happily into both reds just as I recorded originally. The output level overall is slightly greater now too, matching the volume I set the Beomaster to for playing cds.

Thanks everyone for chipping in and thanks ultimately to Steve for providing the donor deck in the first place.

Re: Beocord 3500 (1988) vu meter

chartz — Fri, 27 May 2011 09:11:57 GMT

Søren Hammer:

I generally have problems with this on all my beocords.

The Beocord 5500, 8004 and my two 9000's do only show a level that is 3-4 dB lower than the recording level, it is quite annoying as the playback level also is reduced compared to original recording levels...

I don't have this problem, Søren!

On the BC9000, after the calibration process, you should record so that the meters don't go over 0 dB, but then on replay they will go over it if the tape can handle high levels. For instance, a metal tape will hit the +5 mark, and with a lesser tape (BASF CrO2) the meters won't go much over the 0 dB mark. But that's just the Beocord 9000!

On other Beocords, like the 8000 (6000) the meters should show exactly what they said while recording if the levels are adjusted correctly, as per the SM.

Re: Beocord 3500 (1988) vu meter

lausvi — Fri, 27 May 2011 08:38:27 GMT

My bet would be on the electrolytic capacitors. I had a faint memory of reading something about the VU meters on these decks in Beocentral Workshop Notebook. Quick search found this:

Beocord 2000

No sound and the level meter showing some segments lit all the time is a common problem with this model. The cause is lack of the 7.5V bias supply which comes from the LM1131C Dolby processor IC. The chip itself is rarely at fault however, the culprit is most commonly one of the two 220uF electrolytic capacitors C208 and C408, they tend to go short circuit. Fortunately the chip usually survives this. The Beocord 3300, 3500 and 4500 use a similar circuit (but with only one capacitor) and so can also suffer with the same complaint. [Beocord 2000]

Not exactly your problem but related to the VU meter and caps. I thought somebody else wrote about those specific caps causing trouble.

Re: Beocord 3500 (1988) vu meter

pepps — Fri, 27 May 2011 06:25:25 GMT

Update: So I took the bonnet off the Beocord and found two little adjuster screw type things underneath the upper PCB. They're laballed 'output level'. They were a smidge off being at full whack, so I turned them to full whack. One screw controls each stereo channel - one for left and one for right. I was able to do this while a tape was playing in the machine. The Peak Programme Meter did raise its game, but only slightly. I'm only getting occaisional flickers into the 4th green cell on recordings that I made myself and know to be big red hitters.

I also adjusted the alignment screws near the playback and record head. This has brought me a slight improvement in clarity but made no improvement to the gain showed on the PPM.

Annoying. So the problem is still unsolved. I keep seeing Beocord 3500s on eBay for about £50. One seller advertised the deck with a video, which clearly showed the PPM hitting the reds without issue. Perhaps it's time to consider just buying another deck.

I hate having to admit defeat though! Thank you all for your contributions.

Re: Beocord 3500 (1988) vu meter

pepps — Wed, 25 May 2011 08:28:02 GMT

Great pic Soren - what a beast!!

Glad to hear I'm not alone with this issue. I'll take Mika's advice and have a little look under the bonnet for any sign of adjustment capability. It'd be good to fix this - it plays on my mind when I'm trying to enjoy my tapes.

Re: Beocord 3500 (1988) vu meter

Søren Hammer — Tue, 24 May 2011 16:51:31 GMT

I generally have problems with this on all my beocords.

The Beocord 5500, 8004 and my two 9000's do only show a level that is 3-4 dB lower than the recording level, it is quite annoying as the playback level also is reduced compared to original recording levels...

Re: Beocord 3500 (1988) vu meter

tournedos — Tue, 24 May 2011 15:55:33 GMT

No, don't touch the bias trimmers, they are for a completely different thing.

I'm going only by the schematic as I've never been inside these decks, but there is a setting for the level meter somewhere. It seems to be common for both playback & record, so it probably isn't your problem if the VU meters work correctly during recording. I suspect the problem is more likely to be a bad solder or something similar, and it may be difficult to locate.

Re: Beocord 3500 (1988) vu meter

pepps — Tue, 24 May 2011 09:22:22 GMT

Hi - thanks for your post. Yes the playback sound is fine, it's just the VU display that's just not hitting high enough.
I did notice a couple of adjuster screws inside the unit, for bias I think, for each tape type setting. Is this what you're referring to?
I've taken the tape mechanism out of the deck many times, perhaps this has had a negative impact on the settings and they do indeed need tweaking?

Bit nervous to start mucking about with settings though....

Re: Beocord 3500 (1988) vu meter

tournedos — Tue, 24 May 2011 07:56:54 GMT

Just to clarify: is the playback sound level OK and the only problem is the VU displays, or are both down from what they should be?

I believe there are separate level settings for both inside the deck, but they're not going to drift that far without some other problem...

Re: Beocord 3500 (1988) vu meter

pepps — Tue, 24 May 2011 07:48:04 GMT

Hi Steffen,

Thanks for your post. An interesting idea but I'm no wizard when it comes to inner electrical gubbins; much more mechanically minded sadly.

I'll wait and see if anyone else comes up something, which seems unlikely.

Re: Beocord 3500 (1988) vu meter

Steffen — Tue, 17 May 2011 18:39:28 GMT

I'm not an expert on this -but it might be because some of the electronic components inside is ageing. Probably some capacitors that need to be replaced.
I have some 20 to 25 years old tapes that still gives full levels on the VU-meters -so I don't think it's the tapes. And -as you say, they sound good and clear...

Re: Beocord 3500 (1988) vu meter

pepps — Tue, 10 May 2011 11:56:21 GMT

Update:

I've since cleaned the deck properly and the sonic aspects are as once were previously, as in my tapes sound good, clear and free from wow and flutter.
The peak level meter is still a worry. As stated before none of my tapes will show the red peaks as they once did (I liked to push the HX-Pro circuit hard and record everything into the red to get good punchy recordings).
I've made several new recordings from both cd and phono linked through my Beomaster 5000. I've used both chrome and ferro tapes (Beocord 3500 wasn't always a good partner for chrome tapes). The record volume slider on my Beocord functions without problems and the LEDs light up without any abnormalities.
The trouble is that after I make a new recording, with peak levels showing with occaisional flicks into the 2nd red LED bank, playback only flickers low down on the green end of the peak level.

Does anyone know if there are internal adjustments on the board I can make to help boost playback levels?

Do I have to accept that my tapes sound ok, they just don't 'look' good?

Re: Beocord 3500 (1988) vu meter

pepps — Thu, 19 Aug 2010 12:19:37 GMT

Hi - thanks for responding.

The tapes don't sound dull, they're in quite a good sonic state. It's just volume that's down. Dolby works well on tapes I've recorded myself.

My tapes are old - about twenty years and more. They've been dragged about from flat to flat over the years and haven't been played. Perhaps you're right.

One thing I haven't done yet is to make a fresh recording and see how that plays back.

I'm currently trying to find a cable that will allow two way travel of signal to and from the Beocord and my amplifier so I can carry out a recording.

Re: Beocord 3500 (1988) vu meter

tournedos — Thu, 19 Aug 2010 11:54:40 GMT

Head alignment mostly affects higher frequencies, which contribute very little to the overall volume, so that's not a likely culprit. Cleaning and demagnetization can't hurt, but it could also be just a matter of your tapes aging, either due to not so optimal storage conditions, or the tapes themselves being not quite cutting edge. Do they sound dark and dull, or are you really only lacking volume? Do the Dolby settings match the ones you used when recording?

Beocord 3500 (1988) Peak Performance Meter

pepps — Thu, 19 Aug 2010 10:29:34 GMT

Greetings all,

I previously posted a cry for help about my Beocord 3500 and gratefully received a heap of support from this forum, thanks all!
I'm still working on improving this deck. It plays tapes well, but I'm now keen to improve playback.

My question is around cleaning and demagnetizing.

When I playback my old tapes, I'm not seeing any 'red' in the vu meter. A lot of the pre-recorded tapes I have would flick into the red now and again, whereas almost all of the tapes I recorded myself would light up the two red indicators as a matter of course (I made the most of the hx-pro system when I used this deck as a teenager).
Now when I playback these tapes I'm getting the first green indicator and peaks up to the third!

Just to check, should I get out the isopropyl and cotton buds and consider tracking down a demagnetizing gizmo? Or does this problem seem more likely to be down to head mis-alignment?

Thanks in advance for reading. I look forward to reading your responses.