Roberts 808D 8-Track Capacitor List
My brother is a 1970s fanatic. When he was an undergrad, he had a disco ball in his dorm room and many 8-tracks to go along with it. For his birthday a couple of years ago, I decided to get him a hi-fi stereo component 8-track player/recorder. Now that my brother had an 8-track player in his Buick, it was time to get something that could record on 8-tracks. (MP3 to 8-track conversion, anyone?) After doing some research, the Roberts “Rheem” 808D (similarly packaged as the AKAI CR-80D) seemed to fit the bill for a good piece of audio equipment. Unfortunately after a few months in service, the audio began to disappear. Since this piece of 8-track hi-fidelity (a paradox?) equipment is around 30 years old, the electrolytic capacitors might be on their way out. As with the Seeburg Sunstar I’m restoring, any electronic device over 30 years old with electrolytic capacitors probably needs all the electrolytic capacitors to be replaced. Since I don’t want to try to hunt down a service manual for the Roberts 808D, I opened up its chassis, noted all the electrolytic capacitors, ordered them and replaced them. If someone else out there is looking to repair their Roberts 808D to listen to their STONE GON’ Barry White 8-track, hopefully this list will help them! I know I wish this list was out there for me to begin with…
Since I don’t have the schematics, I can’t properly designate the PCBs (Printed Circuit Boards) or capacitors. So, I’ll have to describe the PCBs in a general way:
Bottom of Unit, “Right PCB”
This PCB has four potentiometers soldered to the back of the PCB as well as the most electrolytic capacitors of all the PCBs. You’ll have to unsolder some wires to work on this PCB, so be sure to take pictures beforehand.
- (2) 47uF 25V Radial
- (6) 10uF 25V Radial (4 of them are 16V, but 25V will sub just fine)
- (6) 33uF 16V Radial
- (4) 4.7uF 25V Radial
- (4) 100uF 25V Radial (2 of them are 6.3V, but 25V will sub just fine)
- (2) 1uF 25V Radial
- (2) 47uF 25V Axial (these are on the back of the PCB)
Bottom of Unit, In Between “Right PCB” and “Left PCB”
Be sure to note positive (+) and negative (-) on this huge capacitor for when you solder in the new capacitor. (In my case, the purple wire was connected to the negative pole.) The resistor that bridges the + and – poles is a 1/2W 220k Ohm carbon resistor. Since the computer grade version of this capacitor was quite expensive, I opted for the “regular” aluminum electrolytic capacitor. Since the “regular” version is much smaller, I used double-backed foam adhesive tape to mount the capacitor to the inside chassis.
- (1) 330uF 160V Computer Grade Radial
Bottom of Unit, “Left PCB”
You’ll have to unsolder some wires to work on this PCB, so be sure to take pictures beforehand. The TO-221 transistor is a Hitachi 1061. I didn’t replace it because it metered OK.
- (2) 100uF 25V Radial (1 of them is 6.3V, but 25V will sub just fine)
- (1) 47uF 50V Radial
Top of Unit, “Motor Capacitor”
I didn’t replace this capacitor as it is relatively very costly and the motor was working fine and at the right speed. This capacitor is the “can type” as it has a metal housing.
- (1) 2.5uF 260VAC Motor Capacitor
Top of Unit, “Upper PCB”
There are a couple of screws that hold this “sliding” PCB in place so be sure to note their position.
- (1) 470uF 10V Radial
Back of Unit, “Power Supply”
For the 1000uF 50V computer grade (CG) capacitor, since it was relatively inexpensive, I opted for it. You could probably substitute a regular, aluminum electrolytic capacitor. I once read that CG capacitors of 30 years ago are probably equivalent to “regular” aluminum electrolytic capacitors today because the technology has advanced. There are noise and value benefits to CG capacitors, but, if you’re not too picky, you should be OK.
- (2) 470uF 25V Radial
- (1) 1000uF 10V Radial
- (1) 1000uF 50V Computer Grade Radial