Sign in   |  Join   |  Help
Click here to tell us about your new email address

Beogram 400x projects

This post has 667 Replies | 5 Followers

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Thread Links
Beogram 4002 Type 5503 and Beogram 4002 Type 5503 (additional info)
Beogram 4002 Type 5523
Beogram 4000 Type 5215

My first B&O product was a Beogram 4002 back in the mid-seventies. It was one of the AC motor types but I don't remember the exact type number. I would have to guess it was a 5503. I ended up having to sell that turntable due to school expenses. As soon as I graduated, my first purchase was another Beogram 4002.  This was a type 5523 that I still have and use. After joining the Beoworld forum to learn about maintaining and repairing my B&O equipment, I discovered the different types of 400x turntables.

This year I was able to find a couple of the type 5503 turntables for restoration and almost have one of them complete. I also hope to soon have a Beogram 4000 restoration project. There is already a lot of great information on the Beogram 4002 turntables - Beolover has a good thread and a blog, Menahem Yachad has an really nice PDF file on Beogram 4002 and 6000 restoration on his Condor Audio web site.
I followed Menahem's guide for most of my repair. However, I didn't replace the lamps with LEDs...not because of anything against LEDs, but because most of the lamps are working and I only needed to fix one.

In this thread I will try to show some differences between the types as I work on them.  I might repeat some information that is already posted but I will try to add to what has already been presented.

This first picture is my Beogram 4002 type 5503 before doing any restoration. It was fairly clean and the motors work. The top piece of the control panel was beginning to come loose.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is another picture that shows the type -


chartz
Top 25 Contributor
Burgundy, France
Posts 3,476
OFFLINE
Gold Member
chartz replied on Fri, Dec 26 2014 7:15 PM

I for one shall eagerly follow this new thread of yours. Smile

Jacques

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

The type 5503 has a CD-4 a muting circuit board that is between the incoming external, phono cable and the Beogram phono signal assembly.
In this picture you can see the phono cable on the left, the CD-4 board and the plug to the tonearm assembly phono wiring (on the right).

Correction: This is the output board and shows the muting relay (and circuit).
 


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

You can see in the previous picture that the external phono cable has four wires (RH, RL, LH, LL) plus a fifth wire that is the cable shield.  Before leaving the Beogram, that phono cable goes inside a second shield wire and jacket. The second shield wire connects to the Beogram chassis and to the DIN plug housing. Note that there is a black wire in the first picture and this picture that is for the amplifier chassis ground. That wire runs outside the cable assembly.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is a little bit better picture of the cable assembly where the outer jacket covers the inner cable.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is a picture of the DIN plug end of the phono cable. The outer jacket shield connects to the metal DIN plug housing and the inner cable wires connect to the DIN plug pins.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member
sonavor replied on Fri, Dec 26 2014 7:56 PM

The reason I am showing some detail on the phono cable is because I might need to create a new one for one of my decks. I haven't found wire cabling with the inner and outer jackets (with shields) so I would likely have to make my own.

Fortunately, cleaning the cable up on this 5503 has resulted in the cable still functioning well.

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

The electrical component replacement is pretty straight forward and documented well in Menahem's PDF guide. 
This is a picture of the big capacitors that I replaced on my 5503 -


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Plus the two orange electrolytic caps in this picture.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

On the main board I replaced the orange electrolytic caps and the red tantalum caps. I also replaced the six resistor pots on the left and the four large resistors on the board. On this board the previous owners used four 47 ohm 1/2 Watt resistors to make one 47 ohm power resistor.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

There were also two tantalums on the trace side of the main board.


Leslie
Top 25 Contributor
the Netherlands City
Posts 5,423
OFFLINE
Silver Member
Leslie replied on Fri, Dec 26 2014 8:32 PM

sonavor:

The type 5503 has a CD-4 board that is between the incoming external, phono cable and the Beogram phono signal assembly.
In this picture you can see the phono cable on the left, the CD-4 board and the plug to the tonearm assembly phono wiring (on the right).

Hi John,

Are you sure the one on the picture is a complete CD4 board? Thought that the CD4 had lots of more electronic components on it. Does your 5503 has a CD4 switch at the right side of the TT?

Will follow your thread with much interest, lots of pictures, that's what I like. 

 

Brengen & Ophalen

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

The two 5503 decks I have both have this smaller CD-4 circuit. There is a full CD-4 and RIAA amp version that is in place of the boards I have. That version was the Beogram 6000 I think.
Also, these 5503 types do not have an adjustment for AC voltage. The switch plate is there but it is empty inside. The deck is fixed for 117 VAC.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

The recap on my 5503 was pretty uneventful. That is a good thing.
On the large power caps, the modern equivalent replacements are much smaller in physical size. I mounted them to the Beogram chassis with some Aleene's glue.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I replaced the smaller tantalum caps with WIMA polyester caps except for a couple places where the space was too small. In that case I used a modern, small electrolytic cap. The other electrolytic caps were replaced with modern equivalents.
The adjustable resistor pots were replaced with some Piher pots. It is important that the replacement pot can be adjusted from underneath as this board goes in the Beogram with the trace side up. The pots are for adjusting the turntable speed, motor gain, forward and reverse speed and sensitivity of the detector arm sensor.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

You can see the darkened PCB under the R1 resistor. I followed how Menahem made sure there was space between the larger wattage resistors and the PCB when he replaced them.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here are the resistor pot adjustments.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

This is the one electrolytic capacitor on the tonearm assembly


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

While the Beogram was apart for the part replacements, I cleaned and lubricated the moving mechanical parts.
After the part replacement it was time for the adjustments. The mechanical adjustments are in section 4 of the service manual.  The electrical are in section 5.

For the mechanical adjustments I installed an MMC 20CL that has a broken stylus. That way I didn't have to worry about damaging a good cartridge.
On the tonearm tracking force adjustment I set the tracking force dial to 1 gram. Then I used a digital scale to measure the tonearm tracking force until it read 1 gram as I turned the calibration screw shown in the picture below. When I had the setting I put a drop of glue on the screw head.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

With B&O turntables and cassette decks, there are some mechanical adjustments that refer to special B&O calibration tools. The "Adjustment of pickup arm Length" is one of those on the Beogram 4002. All I could do is kind of eyeball the positions with the help of a straight edge.
It would be nice if someone has any of the adjustment tools to take precise measurements so we could make some replacements.

Here is the service manual excerpt I am referring to -


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I was lucky as I didn't find any adjustments necessary on my 5503 other than the tracking force calibration.
The tonearm lowering speed seems okay and the shutter control that regulates the tonearm drive servo operates as the service manual states.

Before making the electrical adjustments, I had a burned out 33 RPM indicator lamp.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I decided to save replacing the Beogram lamps with LEDs for one of my other Beogram 4002 restorations. On this one I just swapped out the display unit with one out of a parts deck (BG4004) that I have.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

For the 45 and 33 RPM speed calibration I used an old, damaged LP I have that I placed reflectors on. I use a strobe meter to detect the reflectors and check the speed. You can see why the adjustment pots need to be accessible from the trace side of the board. 


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I didn't take any photographs of the motor amplifier output voltage adjustment. I'll try to remember and add one later. The adjustment is to measure the output signal to the motor (AC voltage) with an oscilloscope and a DVM. The oscilloscope will show the quality of the signal and the DVM will show the voltage (RMS).  The adjustment is to adjust the motor control pot so you get the largest output you can with a good clean (no clipping) sine wave.  The minimum acceptable voltage is 4.5 Vrms.  My 5503 adjusted to 7 Vrms.

The forward and reverse speed adjustments show adjusting the respective pots while measuring MR and MB. That isn't clear to me where that is on the board so I skipped that adjustment.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I also didn't adjust the detector arm sensitivity.  The detector is currently set where it will sense a black vinyl record and can sense when there isn't one. The sensitivity adjustment allows you so compensate for vinyl discs that are transparent. I will come back and check this sensitivity later once I am about ready to put this turntable into regular use.

With all of the adjustments made. It is time to try out some vinyl. 
I installed an MMC 4000 cartridge that I have as a spare and tested the play with one of my older records (Bruce Springsteen "Darkness on the Edge of Town").
It played through great. Set down and lift off was perfect. I will keep adding to this post as I collect more information on this 5503 type and dig in to some maintenance on my 5523 type (DC motor).  I also hope my Beogram 4000 arrives in good shape.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I ran the motor amplifier output voltage check again. The picture shows where you connect the oscilloscope probe. The DVM probe also attaches to the same spot. I didn't use my DVM this time and just checked the values measured by the scope.  The scope probe ground is attached to the PCB 1 ground.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is the motor amplifier output for 33 RPM


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is the output for 45 RPM (you can see the sine wave frequency is faster)


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

I am ready to put this 5503 type into service so tonight I worked on getting it all back together.
First I have to fix the control panel which had come apart.  Here are the pieces that make up the control panel housing.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Control panel glued back together


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

...and with the control board slid into place


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member
sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

This Beogram has had some rough moments. The dust cover is decent enough to use but has a lot of scratches. Even the best recommended scratch remover can't make it look new again. The rear of the cover had some chipped paint spots so I can at least cover those up.
When the paint is dry tomorrow I will start using this Beogram.


Rich
Top 50 Contributor
Orlando, Florida, USA
Posts 2,528
OFFLINE
Bronze Member
Rich replied on Sat, Dec 27 2014 11:36 AM
sonavor:

...and with the control board slid into place

If that's the same board from the very first photo of the thread, where did the "finger print" go?

Most excellent thread, of course.

Blah blah blah, blah blah ba ran

Søren Mexico
Top 10 Contributor
Mexico City
Posts 5,904
OFFLINE
Bronze Member

sonavor:
It would be nice if someone has any of the adjustment tools to take precise measurements so we could make some replacements.

The adjustment tool here mentioned is a simple to make tool, The groove "C" is exactly center of platter shaft. The 2 pins "A" are at exactly 90° to groove "C", 

Do the parallel adjustment first.

A simple way to check arm length is: On a fine black sewing thread make a loop at one end, hook the loop over the platter shaft, pull out the thread to the tonearm, lower the arm and place the thread exactly at the needle point,keep the thread fixed in this position. Run the arm to the position shown in the sketch lower the arm, if the needle hit the thread you are OK, if not adjust accordingly,

Collecting Vintage B&O is not a hobby, its a lifestyle.

John Francis
Top 500 Contributor
USA
Posts 130
OFFLINE
Silver Member

Really great thread John. I will find it helpful in completing my own Beogram 4002 type 5503 work.

John

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member
sonavor replied on Sat, Dec 27 2014 4:41 PM

Rich:


sonavor:


...and with the control board slid into place



If that's the same board from the very first photo of the thread, where did the "finger print" go?

Most excellent thread, of course.


I didn't mention it but while the control panel plate was off, I took a "Magic Eraser" to it.  Then I sprayed it lightly with some clear finish. After that dried I sanded it again. The result turned out pretty good I think.

sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Here is the 5503 type back in play.  The only disappointing thing about this one is it has a few physical defects that I will have to live with - The dust cover isn't as I would like it (it's about a 5 out of 10) and the platter has some markings that can't really be cleaned up. The important thing is that it performs its job though and it is doing that really well.


sonavor
Top 50 Contributor
Texas, United States
Posts 2,636
OFFLINE
Gold Member

Now that I have a working Beogram 4002 type 5503 I can pull my type 5523 and do some maintenance on it. The 5523 is one I purchased new back in 1977. It was a great turntable for me through 1983 when I bought a Beogram 8002. The 5523 remained connected to my system for a few more years, then I packed it up. As many know, it isn't a good idea to put these machines into storage. They need to be used regularly. 

When I brought the 4002 out of storage (sometime in the late 90's), it no longer worked.  This was before I began this audio restoration hobby so I sent it off to a restorer called Beomuse. The gentleman did a great job and I have been able to use the turntable ever since. Lately I have noticed a slight hum through the 5523 when connected to a preamp so the phono cable is one thing I will look at.

Here is my 5523 before moving it to my workbench.


Page 1 of 17 (668 items) 1 2 3 4 5 Next > ... Last » | RSS