ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
A new challange has been thrown down at the weekend! symptoms are channel fading on one side.....will get the manual out and read up..........
Ok....getting back to this one now Roasties BG4000 has been dispatched, connected my Ipad up to the AUX input and played a tune....got a very poor weak sound from the speaker 2 outputs....bit concerned I plugged the Ipad into the TAPE input and the sound reproduction is very good. Cant detect any fading from either channel...in fact it sounds very nice. will try speaker 1 outputs with a centre speaker too and see how that goes.....not sure why the AUX input isn't happy with the Ipad…..
This is the Beolab 5000 that Frede restored for me in 2008. Been serving up sterling work for some time now but suddenly developed a fault - may well be the Aux in...
Peter
Was over in your neck of the woods last weekend, drove right past Earsdon on my way to a wedding in Whitley Bay......lovely place ;¬)
You should have popped in! I could have given you another VCR ! Have a wonderful V2000 model looking for a home!
popped the top off for a look inside, bit dusty but otherwise in very good shape....all previously recapped. Power supply, Driver Stage Left and Right
Pre Amps, Amps II, Tone Control Amps left & Right.
Pushbuttons, Filters,more Amps and Level Control.....
Very compact in there....will give it a clean and make a start tracing a signal through the AUX input, see how it looks
Interesting seeing a unit from Classic Audio from the inside, check the switches, I had to clean the switches various times on the 2 units I restored
Collecting Vintage B&O is not a hobby, its a lifestyle.
It looks like Frede put some extra protection over the switch assembly
Pic from my first one, observe the switches, no cover
Cant say I see the covers you refer to Soren...is it that the switch sliders on Peters Machine are grey in colour as opposed to black?
Ok....looking at the service manual it tells me that the AUX input and the PHONO input on HIGH impedance setting both take the same path into the amplification sections.
Poor image...sorry, however when I connect my iPAD to the PHONO on HIGH impedance I get a nice mellow sound from the amp....connecting back to the AUX and I'm getting almost nothing.....I'm thinking that the problem is narrowed down to the AUX socket or as Soren advises the selector switches. I think its time to employ the faithful old scope yet again.....£20 from ebay a couple of years ago, what a good buy its turned out to be ;¬)
Craig: Cant say I see the covers you refer to Soren...is it that the switch sliders on Peters Machine are grey in colour as opposed to black?
Yes it must be gray switch sliders, in the 2 units I have seen they are black
Found something a little odd....when injecting a 4khz signal through PHONO set HIGH the signal at the AMP II input to the base of the first transistor (no tag identifiers on the components in this machine) was very clean, injected the same signal using AUX input and got nothing at the same transistor base...took a look at the 5 pin DIN plugs and found the PHONO is wired across pins 2/5/3......PHONO socket is second from the left in the pic with the grey/white connections.
However.....the AUX connections are wired to terminals 1/2/4 of the 5 pin DIN socket, 4th from left with the yellow/white wiring, so clearly the 5 pin DIN plug I'm using to connect to the AUX isn't wired up in sync with this socket, but its good for the PHONO......
This is perfectly correct according to the service manual...….but how odd, is there a reason for this? cant see the boys at B&O doing this just for the hell of it.....I will the AUX in accordance with the PHONO socket for testing purposes and leave it like that unless anyone can explain why this should be so?
Connected my signal generator directly into the AUX phono jacks that sit above the 5 pin DIN, injected 4khz at 1v pp and got a sweet output on both channels....next step will be to have a look at the signals coming out of each chanel for signs of distortion/clipping.....see if anything is amis.
had these little fellows delivered this morning....
so promptly removed the front and all the switch buttons to expose the slide potentiometers, bit dusty as you would expect so some cleaning to be done before application of the two greases.
unfortunately I will be flying off tomorrow, I can be found windsurfing off the coast of Greece by day....and in the bars and restaurants of Vasiliki by night! tough life I know......any hints or tips would be nice to read up on my return, may even drop in occasionally over the next two weeks whilst sipping cold beer at the beach bar ;¬)
Have a wonderful time - hope the weather is kind to you!
Following a very hard two weeks on the water I'm back, I keep telling myself this will be the last time I go windsurfing....but my partner is now getting very good at it and I fear I may have created a monster! not to worry....got the slider tracks lubricated with graphite grease and the guide rods given a coat of silicon grease. Started to reassemble by reconnecting the sliders to the front frame....been a few weeks since I disassembled this so some care will be required.
Welcome back, is it true that windsurfing cures the Beovirus ?
Cheers Soren.....however I dont think there is a cure for our particular ailment ;¬)
front panel re assembled complete with slider cursers and pushbuttons, powered up and time to check the no load current. It is in remarkably good condition, I have been reading Sorens thread and there is no comparison between the condition of Peters machine and that of the machine Soren restored when he first took delivery.
Following the application of the silicone grease on the slider pot guide posts the cursers move more slowly to the touch and feel somehow more stable, more precise if that makes any sense.
Left stage measures up pretty good at 6.2mV across R460
Right stage looked a little high at 7.5mV
Tweeked it down a little...……...
Right symmetry voltage...looks good
Left symmetry also looking good....and quite frankly it all sounds very good too, cant really find anything amis with this amp.....it sounds great!
Well Peter...if it isn't broke don't fix it, I'm just going to box her up and enjoy her until your down this way again to collect.....there's no rush ;¬)
Craig