Hi all,

I was able to come by a Beocenter 7700 locally. Excited though it definitely needs a tune up and a good cleaning. The unit turns on when plugged in.

Some of the issues are the led readout showing in fragments and the tonearm only moving to the record without lowering down and then returning to its resting place. I've tried adjusting the weight of the tonearm but it seems very loose. So loose that it jiggles with the platter with more force. Though the platter will spin with a record on it without it moving.

Lastly the control panel door will not stay shut down.

I'm guessing that I need to replace the caps and light bulbs in this to make it good as new. Does one know where to get ahold of either of these? Though I'm not quite sure what would cause the tonearm to be off kilter or how to fix the door hinge.

Thanks for any advice,

Ashley

Martin Olsen (Dillen) can supply you with the cap kits, belts etc. I have used his services many times with good results.

BTW I picked up a Beocenter 7700 myself a few weeks ago and plan its overhaul next month. I will need to order cassette belts from Dillen myself soon.

Oh good, thanks for letting me know. I'll be sure to contact Martin.

It really is a nifty machine, I can tell already how well designed it is.

I just bought one to mine was a little scuffed up had some marks and scratches but it works great exept the tape player does not but everything else works fine as for the control panel it may be the latch on the front undernieth the lid maybe broke off look there first (don't know were could find one if it is broke though) i have i different problem mine i can open but it doesnt raise by it self like it is supposed to if you don't have a sevice manual & owners maual  i would suggest getting one you can get them here if you are a paying member they will worth getting would help you with disassemling and reassemly if you need to on this .   Good luck   Roger

The problem with the record player is I think a well known problem. There is a very small metal pin going from the underside of the record player top plate to the upper side at the rear of the tone-arm. This is the arm-lift. This pin is for lowering the arm to the record. After several years the grease that is used for lubricating the pin dries up and the pin does not move anymore. Use a little alcohol to get it running again and the arm-lift will work again!

My tonearm now lowers to the record and returns at the end of the record with no fault. I was in contact with Dillen who helped diagnose a few issues and non-issues. He told me it was most likely the oxidation on the contacts wearing off or loosened up grease after me trying the tonearm so many times. I was also able to put the tracking weight on point at 1.2g instead of the 1.5g I thought it was for the BC7700. I am going to try to clean up a bit (check that pin) since it has been sitting for the last 30 years or so.

As for the lights, I learned that the large red LED display are its own separate component that would need to be worked on, which I understand is a very detailed process. But if I were able to just find another working display of another BC7700 then, that I could swap them for a smoother process. So far, I am fine with a few lines missing from the display as I can make them out for use. Eventually when I find this beocenter for parts, I will try fixing the display.

I'm going over the service manual, to see how to fix the control panel door. I see that there is a black latch (friction plate, #2038) at the rear of the door that seems to be cracked. I am able to push the whole door down with much force feeling like something else would break, then it rises back to open about 20%. I'm not sure if it's normal, but the control panel door lifts up more than the record player dust cover.

It make sense that there is another latch at the front to keep it shut. From the service manual, I see it could be #2041, which is a lock it says. It is not an issue that keeps the unit from working, only visual and I can make sure to take extra of cleaning for dust. I'll keep trying with this one.

My tape deck doesn't seem to work, when I start it, I see and hear a large click of the metal mechanism. The metal part seems to grasps the tape but then retracts from it. I doubt that I am going to use it as much as I will the record player so probably a later project along with the display.

This forum has been a big help to me already and very welcoming. Hope you all enjoyed a great Christmas.

Belts probably on the cassete deck I ordered mine from Martin just the other day because mine does the same thing which i hope won't be hard the way he explained

I order my cassette belts from Dillen as well, plus I already have all the capacitors I need for the recap. Probably start the refurb next week.

The cassette belts should not be to dificult a couple mounting screws and a nd a few pin plug ins will need dicconnected then the tape mechanism will pull out. I have replaced belts on a Beocenter 7000. The 7700 looks very similar.

So you don't need to unsodlier any thing correct? just unplug some wires then? any trouble with the programing door opening all the way mine only opens about 1 inch supposed to open all the way by itself ive heard maybe a clean and lube ya think? dust cover on turntable also same thing but it opens half way

I'll add tape belts to the caps kit then. Thanks.

I beleive my control panel door is due to a broken hinge as I can see a clear crack in it. I have yet to plug my beocenter to speakers but will do so this week.

My doors open about halfway and then they need an assist the rest of the way. prety sure thats kind of how it was when it was new, most likely the grease down in the hinge mechanism is still ok. One thing that happen on the tape side is the lid alignment goes away in part because of the back  spreing pushing against it for twenty  + years. Also the roll hinge pins At the back of the lid become out of kilter - again from the backspring pressure. The screws just mount into the plastic frame and break free allowing the pins to move.

No unsoldering needed in removing the tape mechanism. Really not that tough a job. The hardest part is cleaning up all the old belt goop.

Is there anything to unplug when you put the 7700 into service position?  looks like 2 screws then it lifts up on one side?.   So the whole cassette mechanism removes to put belts on then? and what do you use to clean the belt residue rubbing alcohol? or something better?

Yes you will have to unplug two dins that feed the line signal from the unit to the power amp board  after you unplug the the two speaker like dines the upper half will lift up so you can set the service stand.

for cleaning the belt goop lube oil 3 in 1 will work or you can use some gasoline. ISP in this case isnt very effective.

Thanks for the nice pictures looks like just thye old standard din plug just like the back of the unit this should help alot then take some screws out then the whole cassette come out? 

I will be selling a MCP 7700 on eBay shortly,  I'll put a link on here if you guys are interested.

Andy T.

Bought mine off Burantek (Jeff) Andy. But Someone else here could use them.

The Two din plugs will need to be disconnected in order to open up the unit for servicing.  A closer look at the pictures will show a couple of wire harnesses feeding the cassette player. Its' PCB is located underneath the turntable as is the radio tuner section.

Hi all,

Nothing to do with the present case by maybe someone can help me:

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I have some trouble with a Beocenter 7700 too.

I can only switch it on/off with the help of the power cable.

The display shows “0” and “P” and additionally some recorder leds on.

It is impossible to control other functions, all the keys doesn’t react.

It looks that the Beocenter boot and then freeze on the mentioned display activities.

Normally it is possible to test the microprocessor with “Stand-By” + “Record” ,  the result should be “0” and “P” for an intact microprocessor. I cannot start the test because the keys don’t react but the display shows actually these both characters (sign that the microprocessor is OK?).

I founded somebody which had exactly the same problem in the Net, but till now I didn’t get any answer.

Any idea where I can look at? Is it possible to reset the microprocessor?

Should I try to disconnect the recorder because of the lighting record leds (removing connection cable internally)?

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Any Help would be appreciated

Best regards

JJ

Eugene:

Bought mine off Burantek (Jeff) Andy. But Someone else here could use them.

Ok Eugene, but HERE's a link for anyone else.

so here is the beginning of my restoration.

Keep us posted Eugene, I just missed out on 2 fifferent 7700 on the bay, to expencive but still looking

Awesome, that looks like my grandfather's workshop. I also have that same Product(RED) iPod. Good luck with your restoration.

I actually ended up buying another BC7700, it's a white one but works so well with not much tinkering. All I need is new speakers, since one is not working and a new needle.

Posted

Hi all,

I had the chance to find the same Beocenter 7700 with a Beogram CD 4500 and a pair of Beovox S2400 in the new appartment I bought.

I'm quite a lucky man.

But I can only got sound with the CD player.

Nor the tuner neither the turntable give sound whereas both seems to works well. The turntable process is ok and I even can hear a tiny sound from the MMC4 but when "reading" the record I still have the music from the CD.

Any program I choose (tuner, PH, TP1 or TP2) I habe sound from the CD wich is connected with the DIN line in/out.

Opening the machine as you did, i don't see any unpluged wire or apparently damaged component.

If anyone can help me, at least if it seems fixable or not...

Thanks in advance,

regards from France,

Guillaume

I dont think you are suppose to use the DIN line in/line out for hooking up external components such as CD iPods etc. It was intended for use with say an equalizer or some other type of prefilter/preamp. Leaving it unplugged will mute the rest of the Beocenter.  There should be a plug that fits in its place. Use the the tape 2 for the CD player instead then see if all the other functions are restored.

I assume that I am deeply ashamed. It was obviously simple. Everything go the right way now.

I'm sincerely gratefull to you, many thanks,

Guillaume