The PHILCO Phorum

It's a long story but since I don't type I'll keep it short.
Part 1 About 6 yrs ago I picked up a 200X @ Ktown for a reasonable price. Got home and gave the hairy eyeball to find that the chassis had been significantly modified. All of the IF transformers had been replaced with standard replacements (no tertiary windings), no IF trimmers under the chassis, and no 10kc filter. This means no hifi. So being the optimist that I am I'll see if I can find some original IF transformers. That didn't work out. Then I started to look at the 201. That might be possible the frequency is a bit higher (175kc vs 260kc) but if I could get the osc coil too that might workout.

Part 2 Started on that. Gary over at PTOTP had a 201 chassis and I asked him what he would want for it. He said that it was too heavy to ship what parts did I need? IF transformers and osc coil. Ok. I asked if he was attending Ktown and he gave a positive reply. Why don't you put the chassis in your van and we'll a cut a deal for the whole thing? OK. A few months go by and Ktown is here. I get there and am hanging at the Philco booth but decide to take wander to see whats for sales around. Get back to the booth and there was 3 IFTs and a osc coil waiting for me. Later settle up w/Gary and got home. Was happy to get the hard to come by parts but still some hurdles to overcome.

Part 3 I was thinking that the phasing of the tertiary windings would critical and sorting the osc coil connections may be little bit of a task too. Mean while I had a bunch of other Philco projects going. A 116X,116B, 660L, 42-854, 16B, several 84b's, 80, 39-80, and 41-300. The 200X has been around for a while! I was talking with Kirk and found that he had done a basement cleanout and gleaned a 200/201X. Originally I wanted to borrow the chassis and or service it for him so I could sort out this 200 w/the wrong IFTs I was getting to build. We ended up working out an arrangement for it.
Part 4 The condition this set well the chassis is pretty good. It's had some repairs done over the years but all done neat, nice and well. The cabinet is kinda rough like a keg of ribbed drywall nails. That's the bad new but the good news is that I have a 200X parts cabinet.

Back to the electronics side of things. There is two different chassis configurations for the 201. One has a bunch bakelite blocks. The other has a phenalic board in the center with a half doz tubular cap on it. This style is the one that shown it the service information. I  found a clue that there was a service bulletin on this set. Eventually I posted over on arf and EGG (Gregg) helped find the sb which was in our library. Just wasn't listed by model but by date first. It's #209 https://philcoradio.com/library/download...es%202.pdf I did find out that there are couple more of the odd sets around. Waiting on some parts to come over the bridge from NJ before I get started on it. Fun begins...

Big order from Sal came in so to thought I get started on the 201. Cursory look told in was pretty good but I was a little troubled by # 98. It's a 70H 10ma choke that supplies the B+ up to the mixer section. Connected right after it is a 4mfd cap. [attachment=24822]
Looked kinda burnt and didn't smell so hot either. Check online and found this:  https://www.aliexpress.com/item/4000879432503.html Philco used high inductance low current chokes. Ron was looking for one years ago for a 600 series set.

A little dusty.[attachment=24818] Gotta get some oms after that dial  [attachment=24819] Got #102 out and cut it open. It was a C/D replacement so no tabs on the bottom. Replaced the innards with a pair or 22mf in series yielding 11mfd @ 900v. Just did it to raise the ripple current rating. The answer to the next question is I'm impatient and lazy. Hopefully in the next day or so I can get the 8 electrolytic caps rebuilt.

Here's #101 it's the tricky one. Blue terminal goes to the + of the 8mfd cap, the silver terminal connects to the junction of the - of the 8mfd cap and the + of the 10mfd @ 50v. The - of the 10mfd @ 50v connects to the tab/shell or to the ct of the hv winding. [attachment=24824] [attachment=24820]

Terry, paint that new choke black and no one will be any the wiser. Nice find!

Terry.
I'm working on the 201X in another thread that has the 10KC filter, where the #70 choke was eaten up by a 4 legged critter. Any chance any of those donor units has it ?

Wow I thought my unit had some issues you got yourself a project there. Look forward to following the thread.
Bob

Hi Bob,

>I'm no expert, but have had good success at restoring 4 other radios. For anyone reading this who is considering there first, I literally learned everything I know by ready countless posts from others on this site and a few others. so you could do it to. I've been saving this one, working up the nerve to dive into it.

>I'm working on the 201X in another thread

I noticed. That was the propulsion for me to get going on the one I've had for a few yrs. I thought it might be of some help.  Didn't realize that there are two different chassis versions and that mine would be the later one in an earlier cabinet. Who would have thunk it? 

To answer your question truth be told I do have an original choke. With being said I'm not sure what is going on with the 201 that I'm work on. It has an iron core choke in it's place. Not sure if it's a updated Philco part used on the later revision. Didn't see a part # on it so for now I think I'm going to hang on the spare.
You could give this site a try: http://www.oldradioparts.com/pg20.htm It's under new management.  I got IFT's and osc from this set a few yrs ago. There's another way to filter out 10kc and that would be to build a r/c filter. It use several resistors and caps in series and parallel. https://www.electronics-tutorials.ws/fil...ter_2.html  The down sides are that there is some insertion lost and it's not directly tunable. I'm not sure why the set needs a 10kc filter. It would seem to me if you just turned back the bandwidth a little it would cut off 10kc and above.

>Wow I thought my unit had some issues you got yourself a project there.

I had the same thought w/your set!

Terry,

I've seen this thread plus the one you posted over at the other place.

I can tell you that the 201X chassis in a 200X cabinet which "azenithnut" owns was formerly owned by me; and before that, by John (rocklandman). I had owned the set for years and had never done anything with it, so it was time for it to move on to someone who might do something with it.

Since you also own one of these hybrids, this (to me anyway) is proof that Philco put together more than one of these hybrid mutts and sent them out to be sold. It also makes sense that yours is a later version chassis. I would assume that Philco did this near the end of the 1935 model year, to get rid of excess 200X cabinets and 201 chassis.

I think you are more knowledgeable on this subject than me, but actually having a 10 kc filter in a high fidelity set makes sense. Let's say you lived in an area where 77 WABC (770 kc) is coming in strong at night. You want to hear Cousin Brucie on Saturday night so you crank up not only the volume, but also the selectivity control for maximum fidelity (NRSC standard notwithstanding). But where you live, WJR in Detroit (760 kc) also comes in strong at night. Let's pretend there is no NRSC standard. So you hear WJR bleeding over into Cousin Brucie's show (adjacent channel interference). The 10 kc filter is there to help keep WJR out of the WABC signal.

With the NRSC standard (Google it), AM stations are limited to a 5 kHz audio bandwidth (they were previously limited to 10, which made the 10 kc filters useful). They may not be useful anymore since NRSC, and could probably be eliminated from your high-fidelity radio.

Actually, Ron, as someone who does a LOT of AM BCB DXing, I can tell you, NRSC or no NRSC, there are times when I am very glad my communications receivers have a crystal filter. I lose some audio fidelity, but at least I can listen to the station I want without interference from an adjacent strong station. (Think:  Splish Splash ! ) This is also a situation where sharply peaked IFs and a well aligned TRF stage before the 1st detector really help.

That's good...I guess...but I still stand by my words.

And with that I bow back out of this thread.

Terry
Thanks for the reply.  I understand about holding on to the other filter .  

I saw the iron core tranny you mention, in the photo you posted. I thought that might be part of the 10 KC filter. That's interesting, since I don't see that as a change they made in any the service bulletins I got from Chuck, hmmm   Any chance you have an inductance meter to measure it with ??

You & Ron make good points, that the 10 kc filter may not be necessary, just was hoping to get it working like original. 

If your going to clean up the chassis, it was quite the chore on mine.  A couple of the RF/IF cans are riveted down and others have the classic Hex head screws ( not sure why). To make cleaning easier, I drilled out the rivetted ones to remove the cans, then used some hex head screws from a bone yard philco to mount back down, They match the others perfect.

 I'll be watching and learning your thread.
[attachment=24855]

Ron,
Oh so you know my secret I really don't know how to find stuff in the library.
Tnx for popping in filling the gaps on the "other" 200/201. So now it's one of two that have appeared out of the woodwork. I thought that there was 3 or 4 of them as pictures would show up every so often when the same one changed hands and my brain would mark it down as one more.

Bob,
Unfortunately an inductance/capacitance meter is something I haven't picked up yet. Most of the test gear I use is from the '50s with the help of some modern way of checking it's accuracy.


Perhaps nowdays the only way the get a 10KC+ signal would be from a LPAM. Over here near Philly there's not much on in terms on music. A lot of talk, sport, news, and the like music not so much on AM. SW offers a few music stations in the evening like WTWW @ 5.085 KC.

I'm not much of a polishing kind of a guy.
Mostly servicing and cleaning as needed. If the IFT grid lead's insulation is failing I'll pull the cans off replace the wiring. Clean the dirt/dust from the trimmers and use a soft Scotch Brite pad the remove the corrosion from the cans. I want it to look pretty original if possible. Will replace the known foul players e cap and foil/paper caps. Check audio transformers, resistors, chokes/field coil, and sm coil. Even though the 70H 10ma didn't look so good nor smell so good it was ok. You are lucky those 6-32 screw in the tops of the IFT can be a little devil to get out without breaking the screw or the ceramic.

Looking good so far!

The 200X goes to college: https://www.ebay.com/itm/362846046261?ha...Swm2pd8Cq8
We didn't have a copy of it in the library. It's from Colliers 12/1/34

That's a neat ad Terry - have never seen that one before.

Have been waiting on some parts to come in but in the mean time tested the tubes. All better than 75% except for the 37 open heater, 6A7 usable as is the 75. The dead 37 wouldn't have been a show stopper just would prevented the shadow meter from working. By all appearances the chassis had been well maintained over the years, just sat round for a long time. The cabinet is a different story.
Still have a couple of blocks to do and a tubular to replace. After that I've the a cloth cord and acorn plug to fit. Then the fun really begins...

After taking a long sabbatical I've gotten back to the 201 chassis. The up date is all the caps are done and resistor are check/replaced. Powered up w/o 5Z3 and the lights in the room didn't go off when the radio when on. Had 410vac either side of center of the hv winding which is good. Tubes lit as did the dial and the sm. Plugged in the mighty U7 with Homer attached to pin 1 of the 5Z3 and the chassis. This is just to see if anything catastrophic a second or so before it happens.

No big surprises. Hv went high up and drifted down to about 385V. A nice hiss was emanating from the speaker. What the heck hooked the 120' dipole to the ant post and had stations galore on BC and SW.
It's been playing for about 4hrs w/o a hiccup Took a look at the voltages on the 42's (output) 365v plt/scn -37v cg.  A little more juice than the average table radio. PT is running cool.

Excellent sounding set! And that's just on the bench. I have two cabinets but neither are usable yet.

I did have a question. I'm missing the shielded wire and switch for the bass control. The parts aren't the problem but I'm not sure where wire exits the chassis. Does it come out by the dial drive? I know it connects the block by the volume control. Does the wire run under the chassis?

The Cousin been on for a bit now coming like he's in the room.

Terry
You may have figured it out already, but that shielded wire for the Bass control comes out the side of the chassis to a switch on the side of the radio (right side in photo). Seems like a goofy way of doing it. Seems like it should be a control on the front.[attachment=27186]

Same here on the sabbatical. To test my unit after replacing many caps, resistors, wires,  I did end up cutting the 10KC filter out and used a high watt 2,000 ohm resistor in place of the choke and wala it work, although the volume was very low  ??

I plan to get back on mine this fall when work slows down. Been extremely busy. It has to be a crime of some kind to not have enough time to work on old radios!

Bob