Model 800b Restoration

Since last posting about my 800b, I've gathered a decent soldering iron, supplies, and the Metal Bonne restoration kit, in addition to Hayseed Hamfest's can capacitors. Now I've got the free time to start as well, after putting it off for some time.

I had thus far cleaned the chassis, removed/cleaned the faceplate and glass, as well as a brief waxing of both chassis and face plate. For the face plate I used dish soap and water, and for the tough stains, Goo gone. The champagne coating, which I'm assuming to be lacquered on, rubbed off on a test spot after vigorous rubbing. The faceplate remains intact elsewhere without any visible fading elsewhere.

As it stands, I will begin work on the first section not too soon after rereading the restoration documents. I will not be powering the unit up until I near the end of the restoration. I simply don't have a variac to bring the caps up slowly, and can always obtain one later finances permitting.

I will follow with some current pictures of the unit and innards shortly, I just want to make sure the pictures will be clear enough.
 
Do the POWER SUPPLY including the Hayseed Hamfest Can Caps 1st. With new caps there is no need to bring it up on a variac. BUT it is strongly recommended you build a DBT and get a variety of bulbs from 100W to 200W. Then after each section or every few parts, power it up and test. Any faults would be in that section, rather than waiting until the whole thing is worked on and powering up and the light goes full bright from a short. Now you have to troubleshoot the whole thing.
 
Do the POWER SUPPLY including the Hayseed Hamfest Can Caps 1st. With new caps there is no need to bring it up on a variac. BUT it is strongly recommended you build a DBT and get a variety of bulbs from 100W to 200W. Then after each section or every few parts, power it up and test. Any faults would be in that section, rather than waiting until the whole thing is worked on and powering up and the light goes full bright from a short. Now you have to troubleshoot the whole thing.
Do the POWER SUPPLY including the Hayseed Hamfest Can Caps 1st. With new caps there is no need to bring it up on a variac. BUT it is strongly recommended you build a DBT and get a variety of bulbs from 100W to 200W. Then after each section or every few parts, power it up and test. Any faults would be in that section, rather than waiting until the whole thing is worked on and powering up and the light goes full bright from a short. Now you have to troubleshoot the whole thing.
Thanks for the tip Larry, I was was just looking at the power supply and was curious when it was I should go about doing HH cans. I will make sure to build a DBT set-up and understand how it functions for the tests before moving to any section after the power supply.
 
DBT or Dim bulb tester is a current limiter, in that if there is a short, the bulb goes full bright taking most of the current flow thru the bulb vs. the unit. Saves a lot of components. For an 800B a 150W to 200W bulb is ideal. If everything is copasthetic, the bulb will go bright for a second or 2 then DIM down as the current surge drops.
 
DBT or Dim bulb tester is a current limiter, in that if there is a short, the bulb goes full bright taking most of the current flow thru the bulb vs. the unit. Saves a lot of components. For an 800B a 150W to 200W bulb is ideal. If everything is copasthetic, the bulb will go bright for a second or 2 then DIM down as the current surge drops.
Thanks for the quick explanation. Is this why you can test each section starting with the power section, to isolate and determine problems?

I'll explore making a DBT tomorrow after work, and the day thereafter I can amend my power section, and install the Hayseed Can Caps. I fudged and installed the individual bias caps in the power section (provided in the Metal Bone kit), without realizing it should have used the fifth can cap. Simple fix after today's practice.

Here is a picture from today's progress on the power section, complete with the new rectifier, and the individual bias caps.
 

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Dolphinsmooth;

Be careful about leaving long un-insulated leads on components. Keep wires as short as possible consistent with good lead dress like the wires were before replacement of parts. Take before pictures so you have a reference point to look back at and make any needed corrections to lead dress. One of the best insulation types available is Teflon sleeving. You can find that a number of sources on-line. Also get some various OD sizes of heat shrink tubing to help cover exposed connections except for points you may need to monitor for evaluation of voltages. Proper lead dress can become very important to maintain immunity to 60Hz or 120Hz hum in the audio.

Joe
 
I wish I would have used the Hayseed Hamfest can caps when I restored my 800B - would have made it MUCH easier and looked better to boot.
 
I wish I would have used the Hayseed Hamfest can caps when I restored my 800B - would have made it MUCH easier and looked better to boot.
Yeah, I'm looking forward to dropping in all the can replacements. Even though I messed up and installed the Metal Bone Individual Bias Caps instead of the Hayseed cap, I'm enjoying the challenge of the wiring. I should probably be finished with the Hayseed Caps and Power Supply by tomorrow afternoon.
 
gguillot; Hayseed now has the option of 2 separate caps for the bias, or a 2 section cap that is a direct fit for the old one. It's a lot better than even 3-4 years ago.
 
Don’t think you messed up with the Metalbone individual bias caps. If you were to remount them end on, you could make enough room to mount the IBAM under the chassis. Space is tight in an 800b.
 
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