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I am trying to find the ground wire within a DIN cable on a Beogram 4000.
The previous owner chopped off the DIN connector and had RCA plugs attached.
There are two unused wires one red and one white, so which is the ground wire? Once I know which one is the ground I know where to go from there and this 7 year long hum will become a memory…… and make my amigo Søren happy. Me too!
Thanks,
Jeff
Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Beogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 4500, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 8004, Beocord 9000, Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century, S-45.2, S-45.2, S-75, S-75, M-75, M-100, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase, B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder
I have this one but I am not sure about the colors, but thats the way it is on my BG 1202, which I had opened for service today.
http://i1218.photobucket.com/albums/dd413/mexnielsen/Photobucket%20Desktop%20-%20SOREN-HP/B%20_%20O/Plugs/Plugbgenglish.jpg
Collecting Vintage B&O is not a hobby, its a lifestyle.
The ground wire is the shielding braid. Always so.
Jacques
Will give that a try in about 5 minutes. Thank you Jacques, as always!
chartz: The ground wire is the shielding braid. Always so.
Jacques,
We have something rather peculiar going on here.
OK coming from the RCA cables are red and white wires, plus a ground wire.
On the right channel the red wire connects with a yellow wire from the 4000, the white wire connects to a blue wire AND the braded ground wire.
On the left channel the red wire connects to a black wire, the white wire connects to the same blue wire as used on the right channel plus the braded ground.
What do you make of this mess?
Nothing to read here; sorry.
Something's definitely wrong. Checked my BG4000, I've got black, clear, and braids, that's it. Forget my previous post, your lead is not original.
I would suggest the yellow wire is the R channel, the black wire is the L channel, the blue wire is the common ground and the braided wire is the chassis ground.
Peter
Peter: I would suggest the yellow wire is the R channel, the black wire is the L channel, the blue wire is the common ground and the braided wire is the chassis ground.
Peter,
I am guessing that whoever did this was attempting to use the outer edge of the RCA plug itself as some sort of ground.
Assuming that you are right, and I do assume this to be correct, that the blue wire is being used as a common, how can I get a FULL ground? Can I just tap into the shield and run a ground wire to my pre-amp?
I had wondered for years why this seemingly groundless Beogram 4000 had such a slight hum as compared to either the Beogram 8000 or 8002 which are un-listenable without a ground.
chartz: Something's definitely wrong. Checked my BG4000, I've got black, clear, and braids, that's it. Forget my previous post, your lead is not original.
as you are still on-line, allow me to re-direct this message to you. I am guessing that whoever did this was attempting to use the outer edge of the RCA plug itself as some sort of ground.
Yellow and black coming from TT is positive, blue must be common (right left channel) ground, and the outer braided shield is chassis ground, the common ground and chassis ground must be separated, and check that chassis ground is connected to chassis on the 4000 (Ohmmeter). When separated, if you want to use RCA plugs, the chassis ground must be connected to chassis on the amp, if used with 5 pin DIN, solder chassis ground to casing on plug.
HAPPY XMAS
Søren Mexico: Yellow and black coming from TT is positive, blue must be common (right left channel) ground, and the outer braided shield is chassis ground, the common ground and chassis ground must be separated, and check that chassis ground is connected to chassis on the 4000 (Ohmmeter). When separated, if you want to use RCA plugs, the chassis ground must be connected to chassis on the amp, if used with 5 pin DIN, solder chassis ground to casing on plug. HAPPY XMAS
Søren,
If I understand you correctly you are saying that I should leave this common (blue) wire arrangement but de-solder the ground mesh wire.
OK, I can do that and then connect a proper ground wire to my pre-amp. The Beogram 8002 is already connected to the amp and I have had very bad results when attempting to connect to turntables to the same ground.
Fortunately the pre-amp also has a ground connection.
I will try to check for the ground situation, but with Christmas just about here and I can smell the pumpkin cheesecake cooking, I don’t know how much time I will have to mess with this issue….. as the family is coming here for Christmas.
And this is just for Søren: You know I love my Beogram 4000, but even with your expertise, avoid them like the plague!
All I had to do was adjust the pick-up at the end of play and all hell broke loose. First the arms moved slowly to the left on their own and refused to stop until I unplugged the 4000. Then the tonearm would not drop (even manually) at the beginning of play, followed by the arms no longer responding to STOP or anything but left or right.
It took HOURS to get the 4000 responding correctly and still I had not adjusted what started this mess in the first place. However patience prevailed and the tonearm drops nice and slowly at the beginning of PLAY and also picks up at the end of play BEFORE returning to rest.
The point is when I touch one thing three others break or fail to work. I mean even mid-play the tonearm would suddenly raise…. It was a nightmare.
Of course it may just be my Beogram 4000 and not the series in general. Lord knows this 4000 has had a lot done to it over the years and much of that, not very good.
Merry Christmas to you as well my friend! And a very Happy New Year!
Yes, separate the mesh wire from the blue one, but check that the mesh wire is connected to chassis ground on the TT, then connect the mesh wire to chassis on preamp and preamp to amp.
Søren Mexico: Yes, separate the mesh wire from the blue one, but check that the mesh wire is connected to chassis ground on the TT, then connect the mesh wire to chassis on preamp and preamp to amp.
OK Søren I got it.
I will tell you that this Rube Goldberg arrangement must have worked to a considerable degree as the hum is barely audible. That said I CAN hear it when the 8002 is selected as it manages to crossover within the pre-amp. (So does the FM, but there is an adjustment for that.)
I am a little crestfallen in that I now know even the cable is incorrect, hence the extra wires….. not to mention the lousy wiring job to the RCA plugs. I had thought my 4000 was in better shape, but reality says differently. Sigh.
In spite of it all this Beogram 4000 sure sounds amazing.
You know, all sincere effort is never in vain. I was absolutely positive that I had a second ground somewhere, either on the pre-amp or the tuner. Turns out the amp doesn’t have a ground, and not surprisingly, neither does the tuner, just the pre-amp. So not wanting to connect two Beograms to the same ground, I decided to leave well enough alone and re-wrap the Beomaster 4000 cord. No real surprise all this juggling things around actually quieted down the hum to almost nothing, but any future “disturbance” will cause a change, no doubt to increase. Whatever. One the positive side, thou it too an eternity, I finally got the 4000 functioning flawlessly: The tonearm drops slowly and in the right position, it tracks perfectly all across the record, and then at the end of play it waits to return to both the right spot and AFTER it raises. Hallelujah! For anyone not familiar with working/adjusting an aging Beogram 4000 is EXACTLY like replacing a burnt out bulb on a very LONG and old sting of Christmas lights wired in series. Everything is out until after say 30 minutes you find the bad bulb, replace it, and everything is lit….. for 5 seconds, then they all go out again. Start to search once more, this time taking an hour to find the bulb, and again success. This time you get 20 minutes of pleasure before it all goes dark again. Finally after who knows how many lights you replaced, they all stay on. Score! Success! There is a God in Heaven! And so it is every time (at least for me) with a Beogram 4000. Merry Christmas to all and a very Happy New Year! Jeff
You know, all sincere effort is never in vain.
I was absolutely positive that I had a second ground somewhere, either on the pre-amp or the tuner. Turns out the amp doesn’t have a ground, and not surprisingly, neither does the tuner, just the pre-amp.
So not wanting to connect two Beograms to the same ground, I decided to leave well enough alone and re-wrap the Beomaster 4000 cord. No real surprise all this juggling things around actually quieted down the hum to almost nothing, but any future “disturbance” will cause a change, no doubt to increase. Whatever.
One the positive side, thou it too an eternity, I finally got the 4000 functioning flawlessly: The tonearm drops slowly and in the right position, it tracks perfectly all across the record, and then at the end of play it waits to return to both the right spot and AFTER it raises. Hallelujah!
For anyone not familiar with working/adjusting an aging Beogram 4000 is EXACTLY like replacing a burnt out bulb on a very LONG and old sting of Christmas lights wired in series. Everything is out until after say 30 minutes you find the bad bulb, replace it, and everything is lit….. for 5 seconds, then they all go out again. Start to search once more, this time taking an hour to find the bulb, and again success. This time you get 20 minutes of pleasure before it all goes dark again.
Finally after who knows how many lights you replaced, they all stay on. Score! Success! There is a God in Heaven! And so it is every time (at least for me) with a Beogram 4000.
Merry Christmas to all and a very Happy New Year!
There is no problem connecting 2 BG grounds to the same, a dedicated ground screw is not needed, any screw on steel chassis will do. I have had hum from BGs connected to preamp ground, but connecting preamp ground to chassis on amp/receiver took care of that.
Hi!
I hope you all had a very fine Christmas!
You know, that has always been a clear advantage of DIN connectors: no need for separate ground wires, and total innocuity to noise.
I have my Beogram 4000 connected to a Beolab 5000 integated, and not only is the preamp dead quiet, there is no hum whatsoever. I have always struggled with RCA plugs and low-level signals.
Inside the DIN plug of my BG 4000, the left and right braids are soldered to pin 2, and the external braid to the DIN chassis. Both braids are linked together Inside the deck with a 47nF cap. Only the external braid is directly connected to the deck's chassis.
chartz: Hi! I hope you all had a very fine Christmas! You know, that has always been a clear advantage of DIN connectors: no need for separate ground wires, and total innocuity to noise. I have my Beogram 4000 connected to a Beolab 5000 integated, and not only is the preamp dead quiet, there is no hum whatsoever. I have always struggled with RCA plugs and low-level signals. Inside the DIN plug of my BG 4000, the left and right braids are soldered to pin 2, and the external braid to the DIN chassis. Both braids are linked together Inside the deck with a 47nF cap. Only the external braid is directly connected to the deck's chassis.
Hi Jacques,
Yes, there is much to be said for the DIN connectors, although less for the speaker connectors.
Happy New Year, my friend!
Søren Mexico: There is no problem connecting 2 BG grounds to the same, a dedicated ground screw is not needed, any screw on steel chassis will do. I have had hum from BGs connected to preamp ground, but connecting preamp ground to chassis on amp/receiver took care of that.
Hi Søren,
I can not even dream of competing with you in the area of electronic knowledge.
However in actual practice connecting a Beogram 8000 and a Beogram 8002 to my Beomaster 4400 produced truly lousy results. No matter how I tried to tighten the nut on the ground screw, it was no good.
I solved this problem using an unneeded phono converter box, required with the Beomaster 4500; one TT connected to the BM 4400 and the other to the converter box, and the problem disappeared.
At present all the commotion of working on the Beogram 4000 got the hum to virtually nothing, so I’m gonna leave it alone. If/when the hum gets annoying I will separate the body ground and run a wire to the back of my McIntosh 2255 amplifier. I’ll let you know when this happens.
For Christmas all my vintage gear was in top form for the family visit, The BeoCenter 9000 started off, followed by the Beogram 4000 and the CDX with the big Mac.
Dinner in the dining room was especially nice with the Beomaster 4400 and Beogram 8000 in rare form.
Made for a nice holiday.
Here is the tree this year….. and it too is vintage, 18 years old brought all the way from sunny Florida.
Hey Jeff
I couldn't help but smile, as I read your frustration about the BG4000. It took me completing 2 or 3 with much frustration to get all my knowledge "ducks-in-a-row". Now when I get one in, I literally attack it for a complete rebuild, no shortcuts or excuses.
That basically takes care of everything, with no comebacks.
Menahem
Menahem Yachad: Hey Jeff I couldn't help but smile, as I read your frustration about the BG4000. It took me completing 2 or 3 with much frustration to get all my knowledge "ducks-in-a-row". Now when I get one in, I literally attack it for a complete rebuild, no shortcuts or excuses. That basically takes care of everything, with no comebacks. Menahem
Hey Menahem,
I thought about you when I wrote about my “experience.”
My Beogram 4000 has not has the easiest life and it shows periodically. Trying to do an adjustment is really a piecemeal repair and that by design is frustrating.
Martin had my 4000 on his bench so the electronics are in good shape, but the mechanicals are worn.
I just couldn’t believe my eyes all the “issues” that cropped up, like the TT refusing to respond to the control panel and that slow unasked for arm creep.
All I wanted to do is stop the tonearm from returning before it lifted….. seemed such an easy adjustment. But noooooooo fix that and then the rest started, and of course the pickup changed after the adjustment.
I remember thinking that I bet YOU wouldn’t have had those problems. However as I need to adjust this TT about once every 3 or 4 years, I am really rusty.
That said, once “fixed” this 4000 is a mechanical delight.
Happy New Year!