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
About 1 year ago I bought in DK a BM 1000 together with a BG 1000, these are the same models as the ones I bought new in 1969, I bought these only for sentimental reasons . I went to DK in May this year to bring both items to Mexico. My son (now living in DK) fell in love with the BG 1000, so I had to leave it in the father land. So the only items I had to bring over here was the BM 1000, a Master de Luxe Present 608 a gift from Martin (more later on this one) and some cartridges from Axel and 1 bought locally in DK.
Here the cleaning story of the BM 1000.
First of all the number, (Martin always want numbers)
The BM is functioning OK, but no lights, so I started taking it apart for cleaning and components needed for rebuilding. Bottom cover comes off with, unscrew 2 screws one side, loosen 2 screws on the other side, pull the cover to the side and lift it out, save the 2 insulation strips. the top cover comes off by unscrewing 2 screws on each side, through holes in the bottom frame and one in the middle of the bottom cover.
Turn the BM around lift of the top cover, here also the the knobs off, pull off, no screws to hold them.
Frequency scale comes off with 2 screws
Then the piano keys came off, also 2 screws
Dusty and dirty.
Both side keys out
The scale background comes out, bending the 3 clips and lift it out, fumbling a little.
To get off the front face pull off the 2 clips. red arrow.
And then unscrew the 4 screws 2 right side 2 left side
Then I took out the lamps, here a pic with scale and different items, the black piece above the lamps is a reflector, remember the placement of that one.
I found out, that the bottom frame with front cover also had to be dismantled
As the keays was working sluggish I wanted to give them a good clean, so the scale drive had to come out too, 2 screws front and 2 screws in the middle frame wall
The big cap comes loose with 1 screw from the bottom, lift it up without braking any wires
To lift up the switch assembly, I had to unscrew 2 screws at the bottom and take out the sidewall, transformer side, unscrew 2 screws holding the transformer from the bottom, the switch assembly has 2 pegs sitting under the inside division wall, loosen 1 screw from the bottom, lift it a little and the assembly comes out, be very careful not to break any wires doing this
Look at all the dirt in there, here the other side, this one comes out easily, just unscrew 2 screws from the bottom, wiggle out the assembly, wires !!!
All the innards was dirty like this
I normally clean it all with a brush and Isopropyl alcohol, but this time I selected to do it with a spray bottle (one of these with a finger triggered pump, that comes with detergent in it), I cleaned the bottle and filled it with IPA, and then sprayed off all the dirt, sprayed a lot into the switches and potentiometers, when good wet I worked all the switches off and on many times, and then a lot of IPA again. The main PCB got a spray and left it to soak a couple of minutes and then sprayed it again until clean. All clean. Give the switches a small drop of grease before attaching the keys.
Now ready to assemble it all again, I thought I could put in the piano keys just like I took them out, but no such luck, I had to attach them one by one
To get them off the steel angle, press down and out on the middle peg (red arrow), and they come off easily, clean, and after positioning the steel angle its easy to assemble one by one. I gave the middle pegs a drop of oil before attaching
All in and ready to connect and adjust the 30 volt feed and the idling current.
The 30 volt feed was down to 24 V and the idle current down to 5 mV, adjusting was very difficult, but after moving the trimmers a bit I got it. The trimmers will be changed with new ones later on, as will lamps and caps., after that I put in the stereo decoder and the rest of the covers, played some different FM stations, checked all functions and switches, had to readjust key positions, but it all works, then connected a BG 1202 and that too worked as it should. Finished
Connecting my type M speakers I saw this little reminder, and that made me think of the new devises you buy today, with some hundreds of watts displayed
Here the other (older) BG 1000 (Piaf (Jeff) has one
Will come back here after changing components.
Collecting Vintage B&O is not a hobby, its a lifestyle.
Nice to see you back at work Søren. It is fun to restore old components we have a history with.
Thanks John, took some time to get the spirit again. More to come
Looks great, :)Dont the or or less the same work myself on several BM1000.Kind of special machine to re-assemble...
My re-capped M75 are my precious diamonds.
Its a joy when they are working. IMO they used better components back then, Except for the lamps everything still works on this one, no scratching potis or switches after cleaning, and most of the old gray caps still within limits. Do you change all electrolytic caps and all lamps on yours when repairing, or just the bad ones.
I have too many of the BM1000´s ( need to get rid of most of them, but they are very difficult to sell in Sweden ) that I dont do total recap.I recap powersupply and sometimes the speaker output, do error check, some very few electrical repairs, change bulbs, general cleaning, cleaning and oiling tuner thread and the mechanics involved, clean potentiometers., and then do good listening test to check the quality of it.Some are in good shape inside, and some BM1000 have been way worse then the images you posted, so the cleaning have taken very very long time.Martin wrote in some post that the grey caps seldom is bad in this model.Checking power supply voltage was a good tip though... Have had a busy summer, so I am still working on my reel BC1200, and after that I will dive into the BC2400 deluxe. both of them will have all rode caps replaced by the time I am finished with themTonight I start the electrical adjutments on the BC12000, kind of hazzle as the eq adjustment is not trim potetionmeters, you have to change components.. C
I always check the voltages and adjust if necessary, and if I find one bad electrolytic cap, I change them all. When you start on your BC 2400 de luxe please post, I have a BC 2000 RtoR waiting for TLC
Sure I will :), that will be fun...but I wont start on the BC2400 until september.Christian
Now I got the parts from Martin, caps and lamp kit, so i took the BM 1000 apart again, and changed all caps that Martin provided.
I am a little surprised, for the 3000 uF he provided 2200 uF, I wonder how this will work, but as I know Martin I put them in where they belong, and tomorrow I will test it. As usual it all came with good installation instructions
As I probably mentioned before, this is to complete the very first B&O system I bought back in 1969 and later sold to buy a car. The Beovox 1000 are still missing, but I will get those too someday.
Old caps out, new in, and some more cleaning was possible.
Here is what came out, also from the multiplex adapter, more to come
Søren Mexico:Old caps out, new in, and some more cleaning was possible.
Great to see you back restoring.
valve1: Søren Mexico:Old caps out, new in, and some more cleaning was possible. Great to see you back restoring.
The virus was quiet for a while, but now its back in full force
Got a bit farther today, checked all caps for polarity one more time, also to freshen up my reading a diagram and follow it on the PCB.
I connected it, Adjusted 30 volt supply (was 34V) adjusted idle current, was difficult, I will have to change the trimmers, left it on with no load for 10 min. adjusted again to 24 mV. Checked the lamp voltage 6.8 V, put in the lamps and voila its living
The scale assembly and lamp reflectors in, speakers connected and radio tuned in to Radio Universal 92.1 Oldies, checked functions, speakers 1 and 2, filters, mono, AFC all working good, no funny sounds adjusting levels and balance.
Selfie, checking for smells and heat the old fashioned way, all good, checking the output transistors with my finger for heat, no problems found, now playing for 1.5 hours, I enjoy being back in the saddle, this BM 1000 sounds good and bring back sweet memories, enjoying the music with a well mixed cuba, I think I deserve that.
//Bo.A long list...
Pleased to meet you Søren!
Jacques
@ Sören,
You have checked the idle current without speakers attached, right?
What happens with your idle current when you attach the speakers? Mine here went straight up from 60 to 166mV.
I found this one the nastiest one to overhaul. All parts are bend on the circuitboards and then soldered.
Beobuddy: I found this one the nastiest one to overhaul. All parts are bend on the circuitboards and then soldered.
Hand-soldered. - From above (component side down), unlike automated "wave"-soldering, that takes place from below (component side up).
Good job as always.And great to see you again, Søren !
Martin
Beobuddy: @ Sören, You have checked the idle current without speakers attached, right? What happens with your idle current when you attach the speakers? Mine here went straight up from 60 to 166mV.
Yes without speakers attached, as I have to change the trimmers, I will try with and without speakers, but as I dont get any heat on the output transistors it should be alright
I use a desolder pump, when the leads are free I cut them off at the hole, then heat the solder again and wiggle until they comes out, mostly they come free very easily. Where possible I cut off the component before desoldering.
Søren Mexico: Selfie, checking for smells and heat the old fashioned way,
Selfie, checking for smells and heat the old fashioned way,
Are you sure you didn't fall asleep working on it?
I want to know how she sounds driving the M70s.
Also, the BG3000 (minus dust cover) has found her new home: as part of my wife's stereo in the cabinet in the living room.
We Grumpy old gourmets tend to close our eyes when tasting or smelling something delicious.
I will set it up with the M70s later, but first I will have to change the 2 idle current trimmers.
Glad to hear the BG 3000 comes to use, was afraid you would store it unused in some closet.
Made my first sale today, sold a BG RX to my nephew, I am not a good salesman I lost money on that one.
Jeff is gonna fix his Beomaster 1000. I don't know when, but I will.
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
Søren Mexico: I use a desolder pump, when the leads are free I cut them off at the hole, then heat the solder again and wiggle until they comes out, mostly they come free very easily. Where possible I cut off the component before desoldering.
I use a Weller WXD2020 with pressure pump to desolder. Any other master normally takes just little time to desolder.
But I also have the experience with traces which starts to float on the board after applying to much heat. So I'm very carefull when I'm desoldering when working on a master with that age. But with the BM1000 the traces appeares to be more thicker than with some later released masters.
But your way of taking the parts out is a way to consider and try.
Normally it shouldn't make any difference with the average amplifiers. Some have a DC blocking capacitor at the output. Others don't have these, but are symmetrical fed and isn't there any voltage at the output when the offset is properly set.
But the BM1000 has a circuit which is attached/located behind the output capacitor. I was wondering if that circuit is influenced by the presence of an attached speaker. The servicemanual doesn't state anything about measuring/setting the idle-current with or without speaker. As I've been told, it wasn't uncommon in these days to set the idle-current with a speaker attached.
The BM1000 I have here, played for just half a hour and became rather warm, almost hot. Idle current was set to less than 60mA (without speaker). One transistor didn't survive this. I took the transistor from the powersupply to get the outputstage working again, but had to re-design the powersupply with a new silicium PNP transistor.
(the ordered germanium AD149 in Berlin appeared to be fake)
Søren Mexico: Glad to hear the BG 3000 comes to use, was afraid you would store it unused in some closet.
It sounds too good (with SP12) to put in a closet. I put it in place of an RX2 I had in that cabinet. The BG3000 works better because the dust cover is easily removed.
My recently restored BM1000 is my most-listened-to audio at present. Cheers Søren!
I just got the trimmers in, and started some serious listening, after adjusting the idle voltage to 24 mV, checking the 30V feed, waiting 15 min. and then did it all again. Checked the 24 mV with volume down, phono on, Tape on FM on no change, speakers connected no change, volume up no change.
Here what I am looking at
Adjusted the boomy bass from the connected Beovox CX 100, and then just listened to Radio universal 92.1 transmitendo desde el centro de la ciudad de Mexico. Then the memories came, No I didnt get tears in my eyes I am a tuff man, and boys dont cry, I was just sitting there enjoying my cuba and the music for about 2 hours, once in a while checking for heat (See Selfie) or smells. I then started checking details. And found this
Bit of paint missing on the volume. And this
On-off button worn a little, and thats it, And I just had to take a pic of this
Top of screen No. so 93 Mhz is No. 20, only Fm on this one, so they put numbers to get a better looking display, the text below is self explaining but mixed English and Danish. I am happy, tomorrow I will place it together with the BG 1000 and test it with the M70s.
They are channel numbers.
Wonderful piece and well done! :-)
Agreed, looks superb Søren well done!
Ben
Thanks Sören for have taken the time to investigate ,
I had a look at the manual from your type BM1000. It has a different outputstage. It has the more popular used 2N3055 or similar type transistor. These days still available.
There isn't a kind of feedback behind the output capacitor at yours. So, the idle-current isn't affected by an attached speaker.
Mine here is the earlier type with the white keys, the 2304 version. The one with the germanium transistors AD149's.
Be aware that this type of amplifier has a positive "grounded" chassis and not the minus as most have. So, check for instance that the positive (+)powersupply capacitorlead is connected to the chassis. Same for the other capacitors connected the chassis.
Beobuddy: Be aware that this type of amplifier has a positive "grounded" chassis and not the minus as most have. So, check for instance that the positive (+)powersupply capacitorlead is connected to the chassis. Same for the other capacitors connected the chassis.
I was checking about the transistors and would have come back to you about it, and pos. grounded chassis gave me a long search in my old files (BM 900, 2400, 4000 and 4400) I thought that I had forgotten which the pos. neg. signs are in the drawings, in my defense I must count, that I am a totally amateur and it is more than one year since I worked on a BM. At last I found out that the BM 1000 is pos. grounded. Anyway I placed the caps as they were before, as the BM played nearly OK before repair.
Where I am a little concerned is that Martin provided 2200 uF caps instead of the original 3000 uF caps, but as the BM has been playing for about 4 hours now it seams to work as it should.
I didnt measure the mA as it would include desoldering resistors. I am also limited to a Digital multimeter, ESR meter and a software oscilloscope, and at times I really has to go searching and read a lot to understand what you profs are talking about
Now beautifully united BM 1000 and BG 1000, connected to Beovox M 70s, and that did it for the sound, in comparison with the CX 100s much better sound, distinctive deep bass and clearer highs, with this connection I could also compare with the BM 4400, the 4400 in "linear" and the 1000 with no filters, Both tuned to the same radio station, to get the same sound on both I had to activate the filters on the BM 1000, figure that. I now connected the BG 1000 (SP6/7) to phono 2, Of course it had to be something Danish, and something special for this occasion. I selected H.C. Lumbye, a record that has moved with me through at least 3 countries and 2 continents.
And here they are happy together
Well done and congratulations. Would you mind posting a wide shot that includes the M70s also? I have a bit of a selfish need to see those girls in action.
Rich: Well done and congratulations. Would you mind posting a wide shot that includes the M70s also? I have a bit of a selfish need to see those girls in action.
Will do, and with some explanation
Here goes
BL 4000 (Center speaker), Computer, Set top box, Bluray all connected to Onkyo, Onkyo and BMs connected to source selector, Source selector out to M70s, BG 5000 to BM 4400, BG 1000 to BM 1000, I have my most played LPs placed behind and beside the BG 5000. The rest of my vintage is spread throughout the house, or waiting for repair. The BGs gets changed frequently to the BG 5000 position to give them some action, but the BG 5000 with MMC2 is my favorite. As I sold my BG RX, very nice looking, I may go hunting for a BG 4002/4. In our dining room I have a Beosound 3000 with BL 8000 and some 300+ CDs (FS insist no more there), I am thinking about installing the CX 100s in the kitchen but as we cook a lot maybe not (grease)
Søren Mexico: I have my most played LPs placed behind and beside the BG 5000.
I have my most played LPs placed behind and beside the BG 5000.
And at the front of the list: Rolling Stones Hot Rocks!
Thanks. That looks something like the mish-mash system currently in the spare bedroom where the girls do their homework and I practice the bass guitar. I only have one "pure" B&O system left in the house, and that's out in the garage. But every system has at least one B&O piece in it.
Forgot to mention, in the lower left corner there is a Sub woofer, only for films and the like, the M70s has enough bass for nearly all my needs
Hi Søren,
Wow! What a set-up!
Son, ya done good!!!!
Thank you for yet another one of your interesting threads, Søren.
Looking at the picture of your nice setup, I was wondering... You write that you use the BL 4000 as center speaker - with your M 70's connected to your Onkyo.How is this active Beolab connected to the amplifier together with passive speakers?
Greetings from Denmark
Steffen