800B in a Metropolitan 16A Cabinet?

[Joseph W Strickland]

Is there room in a cabinet originally made for a Metropolitan 16A to install an 800B chassis set and have the slide out feature, or would it have to be stationary without the slide brackets? Or would it fit at all?

I saw this one on eBay and contacted the seller to get a picture straight on of the radio-tuner chassis area: Item # 272578888450

[Joseph W Strickland]

As it turned out, using a steel plate to support the 800B tuner in a Metropolitan cabinet of this type does not work. The 800B tuner chassis turns out to be significantly taller than that of the Metropolitan tuner. I thought I had it covered until I pushed the tuner forward and then the chrome plated piece that supports the commutator disc and moveable preset tabs bumped against the top of the cabinet. It lacked about 1/2 inch all together.

I had some angle metal that was 1.25" X 1.25" by 4ft. I cut pieces of it with a diamond cutting disc on my miter saw. I made sure to use safety goggles because sparks fly all over even with the normal miter saw shields in place. I had to completely remove the wooden rails in the cabinet that originally supported a Metropolitan chassis. This would allow the steel angle rails to be at least a full 1/2" lower in the cabinet. I used the wooden rails to determine drill hole points in the steel brackets I had made. I did a trial mounting and found that there was still about 3/16" of the commutator bracket that was bumping against the top of the cabinet. So - I had to remove the sliding door pieces, used my stationary belt sander to gradually remove enough material from the wooden slide guides on the portion of the sliding door assembly that always remains inside the cabinet. I had to make its vertical height less by the needed 3/16" or so.

I also found it necessary to re-install the door after the internal part had been shaved down, use some poster board strips as spacers and mount the angle brackets. That way after the brackets had been fastened down to the cabinet walls, I could slide the strips out and there was enough play for the parts to move relatively freely. I still need to do some sanding inside the cabinet to eliminate some final binding in a few spots.

I was able to determine the final position of the front wooden trim panel after the tuner chassis was slid into place as forward as it could go without having the front door bump against the knobs of the tuner.

The final result will work and the cabinet will look as it did originally except for the wood trim panel of the 800B tuner. A lot of modifying of the cabinet became necessary in order to get the tuner chassis to fit in this cabinet. The rear top corner braces have to be unscrewed and removed in order to get the tuner chassis to slide in. These will go back in the cabinet after the tuner chassis is in its final position, but will be left without glue on them so that they can be removed again if service requires the tuner to be pulled out. This is definitely not a project for the faint of heart! However, I was able to obtain and save a beautiful cabinet. Cabinets for 800B sets are not readily available minus their electronic chassis. Many of them do have significant damage after so many years. It takes a really dedicated, experienced and determined person to properly restore a cabinet with veneer that is peeling or warped etc. I have been following some restorations of cabinets on-line and I don't feel quite that brave yet.

I will try to get some pictures after I manage to get the final fit of all the parts worked out and in place.

Joe

[Joseph W Strickland]

After long delays due to having surgery for cancer, I am finally back to my hobby restoring vintage radios! I was fortunate to discover the cancer early enough to have surgery and get rid of it. The pathology report and subsequent PET and CT scans show no evidence of it having spread.

I did manage to get the 800B tuner chassis to fit into the cabinet after I added 1/2 inch thick shims underneath the cabinet top which came off with the removal of some screws holding wooden cleats to the underside of the top. Some red mahogany stain on the mahogany shims and then some clear lacquer over the outside finish sides of the shims worked very well and look like they are part of the original construction of the cabinet.

Mike Hadley had sent me some electrolytic empty cans to use in the 800B power supply to replace the bad first electrolytic (a 4uF right after the rectifier tubes). The old one had started leaking material on the chassis bottom cover and corroded the steel plate. Fortunately I was able to remove most of the corrosion. Removing the old electrolytic was quite a task. It began to slip on the top side of the chassis and the retaining nut and starwasher underneath would not loosen. I finally had to destroy the old capacitor and as a result needed a replacement can to stuff and make a new one. Mike came to my rescue and sent me a couple of empty cans and adapter aluminum discs for the bottom to permit remounting on the chassis. I just today found the needed size of hardware for mounting the assembly to the chassis again and bought the needed pieces. I plan to increase the 1st electrolytic value to 20uF which is well within the capability of the rectifier tubes to handle. This will bump up the B+ some and then I plan to try a 100 ohm 10W resistor in series with the B+ to the next electrolytic in the B+ string. I can measure the voltage drop and calculate the current through it, then find the nearest standard value resistor which will handle the current and drop the B+ back down to the original values shown in the E H Scott schematics.

I did manage to find some decent speaker grill cloth and got the speaker mounted in the cabinet. Hope to get the unit finished next month so I can work on other items.

Joe

Here you can see some felt I added under the angle metal rails that support the radio tuner chassis. The felt helps avoid scratching the back side of the front door as it slides under the tuner chassis. It took considerable work trimming, using thin shims etc. to get the rails spaced just high enough to clear the door as it slides in and out. The top of the preset tuning assembly just clears under the top of the cabinet by about 3/16". I still have to stain the back cover over the speaker area and add some internal padding.

Here you can see the crossover network. and the wires to/from the speaker.

[David C. Poland]

Quite a project. Looks nice. 

Glad you are back to good health again.

[Joseph W Strickland]

David;

Thanks indeed! I am very fortunate to have dodged the cancer bullet for a third time in my life.

I still have to put the triangular corner braces back in position behind the tuner chassis and do some other minor things. I may trim the excess felt off of the angle metal rails and make that neater. After I get the cover on the back of the speaker cabinet stained and then put the original thin cover over that it will look pretty original except for the bass reflex port opening to the rear. There remains also the trim veneer on either side of the tuner front panel and a trim piece above that to prevent the door from pushing back too far when the door is closed over the tuner - details, details.

I had delays in getting some things that I needed to bring the 800B together, so in the meantime I had restored a Fisher 202-R AM-FM tuner from their 1962 product line. It had a broken AM ferrite rod antenna when I received it and the FM reception was very poor. I replaced two capacitors in the FM IF and did an alignment plus new tubes , power supply rebuild, replacement of off value resistors and capacitor and now it works as good as new. That kept me in better spirits as I dealt with the cancer issue.

Joe

[Joseph W Strickland]

Thanks to Mike Hadley, I managed to make a replacement for the first can electrolytic of the 800B power supply. The original was a 4uF unit. The previous owner had installed a 4uF axial lead unit under the chassis and it has been operating OK from the first day I received the two-chassis 800B unit. Some months ago I discovered that bridging the 4uF with a 16uF non-polarized polypropylene AC motor capacitor eliminated the residual hum that I was hearing from the speaker. Mike sent me some electrolytic empty cans that are just a little shorter than the original can electrolytic. I used one of them to make a container for the 16uF capacitor that I had to add in parallel with the existing 4uF axial lead capacitor under the chassis. The result is a 20uF first capacitor section after the rectifier tubes. The rectifier tubes are capable of this much capacitance and more, but 20uF does deliver essentially hum free audio from this unit. Here are a couple of pictures with the new capacitor installed.

Joe

[mike hadley]

Nice job Joe, looks like it's always been there
Mike

[Jon Ketron]

Coming together Joe!  Thanks for sharing an update.  Looks great.

Jon