[David B]

Hello:

I am restoring a Philco 620, last night I removed part 66, a 6287 DU Bakelite block so as to rebuild it. I don't have a lot of experience repairing radios but though that rebuilding the block would be easy. Whale this looks like a bit more than I bargained for so my questions is, how do I rebuild this thing. As part of a cap kit I have for the radio there are two orange square caps .015k which apparently are to replace the two caps in the block.

While digging the tar out of the block I inadvertently riped the existing caps out of it. While examining the inside of the block I noted that there are three wires inside the block, apparently they are soldered to the center lugs of the block. How do I wire my two .015 caps in to the block.
Please you help on rebuilding the block is greatly appreciated. Thank you.

Dave

[PhilcoPhil]

Hello,
I hope this link will help you.. http://www.philcorepairbench.com/bblokcap.htm

Good Luck and have fun!!! Phil

[David B]

Phil:

Thanks, but I have the info from the site you provided. The information on the chart may be obvious to you who work on radios on a regular bases, but it' not obvious to me. From what I understand and from the information provided I think I am supposed to take my two new orange square caps, each .15uf, and wire them in parrell. But my question is; of the three wires inside the bakelite block, which ones am I to connect to the two ends of the new parrell caps? Thank you

[TonyJSenior]

David:

The caps actually are more in a series configuration inside those blocks with the common connection of them getting connected to the chassis. You take one leg from each of the two caps and connect to the bakelight lug (wire) that ultimately connects to the chassis via the mounting hardware. The remaining ends of the caps each go to their own respective lugs (wires). Hope that helps.

Tony

[49Stude63]

I will check my Philco condensor block book tonight but some of these have a resistor along with the capacitors. Probably the orange squares sound to be more like the orange dips but the yellow mylars will also fit into the bakelite blocks with not problems. The 6287 series has a ground lug and if you look at the link given you will see three round holes in the center area, each 0.15uf cap will have a leg in the first hole closest to the ground lug (marked #1) and then the first cap will have it's other leg in the 2nd hole and the second cap will have it's second leg in the third hole. I have to see but I think the 6287DU is one of the universal types but as I said I will check that and let you know. I don't try to connect to the old wires, just clip those out and solder the leads to the brass eyelets.

[David B]

THanks, I'll await your reply

[49Stude63]

I looked it up and on page 2-30 6287-DU has two 0.15 uf caps installed as I described. The end that where the bakelite block mounts to the chassis is pin #1 and it will have 6 terminals 3 on one side and 3 on the opposite side. all 6 of these terminals mount to 3 brass eyelets in the middle of the block. Take both of your 0.15 caps and put one leg of each cap into the eyelet closest to pin #1 then take the other leg of cap 1 and put the second let though the middle eyelet and the 2nd leg of the 2nd cap and put it into the eyelet farthest from the #1 pin. Pin #1 is grounded so if you have connections to the 2 lugs farthest from pin #1 the circuit will see 0.15uf and if you have connections to the middle lugs it will also see 0.15uf and you can have connections to the 1st set of lugs from pin #1 and these connections will be to chassis ground. Situate the caps and solder the cap leads to the eyelets and clip off the excess leads.

[Texasrocker]

No disrespect intended to keeping "originality" under chassis to vintage radios, but "why",..... intentionally rebuild a old nasty Philco bakelight "mystery cap"? I can see where newbies could really learn from the experience, however, replacing those special-order only by authorized Philco dealers "part # only" mystery dealer parts days are long gone. I myself had to purchase the "Philco condensers & more" book to help decipher the many individual components originally "tarred & feathered" by Philco. Personally, when I recap a vintage Philco chassis, I chunk the old "mystery caps" (that took up much un-needed under chassis space) and replace them with a new modern type small "terminal strip" with all point-to-point connections added, and use well-marked (values) of modern replacement components to rid the need of having to "guess" , or have to purchase a reprinted book to repair vintage radios. I restore many, many vintage tube radios, and always replace the "mystery caps" so the next generation of restorers never have to be confused. Re-stuffing orig caps is rediculous IMO, and once you get those old orig bakelight housings out of the way, the orig screw-hole in the chassis can be used to mount a new "fully-visable" terminal strip in most cases. I have rebuilt several A-K power units in my days, and "digging tar" to get to components was never a "good-idea" in the 1st place. Now, all you "purists" can chunk rocks at me, but I will also throw many orig bakelight blocks back , or better yet, if you want to re-stuff em, I have plenty in a cardboard box under my bench if you want em. Just my .02, TR

[Ron Ramirez]

Texasrocker, before you throw any more bakelite blocks away, please throw them MY way...seriously...thanks.

[AI2V]

It a simple matter of practice to rebuild those blocks; even with terribly arthritic hands I can completely empty, clean out, and have ready to install caps in less than 3 minutes. It's important that the blocks remain since they serve as terminals and tie points for the wiring; without them the underside will look like a disaster of flying joints.

A heat gun, a small screwdriver, a soldering iron, a small drill bit, a glue brush, and some acetone are the only materials needed- along with the schematic diagram.

First, draw yourself a simple picture of the wiring to the block before removing it. Once removed........

With the tar side up, simply heat the block until the edges of the tar melt slightly; pry off the top 1/8 inch of tar, exposing the caps. Gouge out the caps carefully so as to not break the shell. All of this should take about 90 seconds. Heat the solder joints with your soldering iron and quickly rap the block on a table to remove all excess solder on each terminal. If you now look carefully at the terminal lugs you can see the remaining cap leads mark or remember which one had two leads.

By hand, push your drill bit through the terminal holes to cut the leads and clean out the hole; and finally, clean the block with acetone and a cut-down glue brush. Total time: under 3 minutes for a new looking empty block. Also, take some serious time to understand the schematic diagram- it was drawn for service people like you and me.

[Chris Drumma]

TexasRocker,
One of the things I like about Philcos is the bakelite blocks. I do restuff all my blocks and enjoy doing it. I do it like AI2V suggested. To each his own I guess. I do see your point about space though.


I would gladly take any blocks you have off your hands also! Ron save some for me!

Chris

[49Stude63]

I have to agree doing the blocks is so easy after you do a couple of the bakelite blocks to me it is so much easier than putting terminal strips in and rewiring the circuit to fit the strips in.

[David B]

My friends:

I did not realize the firestorm this issue would produce. I rebuilt the block and it took me more than 3 minutes, but this was the first time around doing it. As to whether or not one should rebuild them is (in my opinion) is a choice, or preference, with either method being equally acceptable and correct. There is no need to throw stones at one another rather let us encourage each other in our endeavor. As to you old timers, please, you are our teachers and the ones who encourage us to undertake these tasks. Share what you can, don't let this talent die with you.

Now for two newbie dumb questions.

1. I am replacing a cap in the radio, one that a former repairer used to do away with part 30 2079, the 8 mfd - 8 mfd condenser. The new caps I have to replace it with are blue colored 10uf caps, with a with arrow and a minus sign in the arrow. Question, does this arrow mean that the direction pointed in is the negative side of the cap? Further, the negative ends of these new caps apparently are to be tied together as a common ground or negative side, correct?

2. I am replacing the part # 30 2118 condenser 16 mfd cap with a new blue 16uf cap. Can you give me some instructions on how to bypass the old can and put this new cap in? Thanks much, have a great day in the Lord.


In the Lord,


Dave

[49Stude63]

LOL no you didn't create a firestorm, and with with rebuilding anything cars, old radios how you do it is up to you since that is your car/radio. On the next topic how to rebuild the electrolytic cans, http://www.philcorepairbench.com/tips/svctip46.htm Here is a service tip from Chuck's site and what you noted about the new lytic being 10uf rather than 8uf is not a problem just make sure the rated voltage is at least equal 450=450 in some case Philco used 500V lytics and you should use the same or better voltage rating for the replacement. On the tip her is if yours lytic can has a paper sleeve it is easy to hide the cut but if you have the free standing center nut mount lytic cans then purchase some shiney metallic duct tape (usually Ace has it) and this can be used to tape the joint, while noticable since you don't have the paper sleeve it is probably easier then cutting the top off and soldering the top back on. If you drill out the rivets that hold the spiral aluminum then you can connect the Positive to the aluminum shaft via a small round headed bolt and nut and then drill a small hole somewhere in the base of the can and run your negative to chassis ground. Your connections all depend on the style of can but since you mention only two uf's 8 & 16 more than likely it has two cans on the chassis and most are center screw base with a nut mount to the chassis. And yes the negative arrow connection is negative but depending on the circuit may not always be connected directly to the chassis ground.

[David B]

Thanks, downloaded information and will follow same.