Hello Guys, I have the mid-chassis out (37-630 late version) on the bench for re-capping and replacing all the old point-to-point brittle cloth wiring. I am using my Riders vol 7 schematic and found a discrepancy. In the front compartment of the mid-chassis Riders schemat calls for a .1 uf, and the orig large philco cap is a .10uf @ 450. ( part # 20 on Riders parts-list on pg # 60 philco 37-630.
The orig philco condenser needing replaced is orig part # (30-4170 P), which the orig part is still in place,(large cardboard tubular) and definately marked: .10 uf/450., and the part # matches in Riders. Was wondering which cap to use in mfds, that is correct, and if I should make a note of this for "correction" in my orig Riders book? Thanks in advance for helping me get the correct part info that should be used. Randal
....my bad.... after closer thought, reading these old caps , my cap in question in my previous post (.10uf), is a modern day .1 uf. Im getting to be a old-fart, and easily confused sometimes! Otherwise, the restoration of my Philco radio continues!!
Randal
I just about have the mid-chassis completed as far as full recap and all new point to point wiring replaced. I left the leads long enough to reach over into main-chassis for their proper connections. I completed full main chassis recapping & all new point to point wiring last week, even back into power-trans internal connections. Did a close check of the power-trans and all voltages are working properly. Waiting for my new repro Philco mid-chassis mounting-grommets to arrive. The contacts are dirty on the band switches. Most of the time I just lubricate switches with good-ol WD-40, and everything works OK. Im wondering if I should buy a spray can of "deox-it" to spray all the contacts with before re-assembly? Is that really necessary? In most cases, WD-40 cant be beat relubing on switches and vol controls. Also, the schemat calls for a #55 dial lamp in the dial-lamp socket. I have almost every other type of dial replacement lamps in-house, except for the #55 round type lamp. I read on Chucks site that the shadowmeter lamp in this 37-630 matches a # 44 dial lamp which I have plenty of in stock. What do you guys use? I probably have one somewhere. Any & all your "tips" would be greatly appreciated! Randal
I use the Type 55 dial lamp in 1936, 37 & 38 Philcos. The large socket & collar assembly was designed for this bulb, and it gives out a bit better light than does the Type 44 in this application. The Type 44 should, as mentioned, be used as the shadowmeter lamp.
Thanks Ron!! I will get a box of new #55 lamps from AES and keep them in-house also. I will use the #44 in the shadowmeter socket. I still have to rewire both lamp-sockets also. The radio is about ready for initial "slow-up" on the variac in the next few days to see if I get audio. Someone in the past really "hacked" it up good installing replacement under-chassis filter caps, wrong caps in wrong places in the past! The radio has a complete point to point rewiring (following Riders), even into the coil-connects in both IF cans. Those old cloth wires were in very bad condition to "crumbling" cloth wiring. I went ahead and pulled both IF cans, and after running new wires, tried my best to remember the lead-dress as orig under chassis. I will have to add a 10 watt wirewound field of 1140 ohms? ( is that correct?), and connect a pm spkr for test after the chassis is all back together. Still flying-by-the-seat-of-my-pants on this one, but it should at least make audio after being-dead for yrs, then I can go from there. Thanks again for all your help!! Sincerely!, Randal
The original field coil of the speaker used in this model was 1140 ohms. If you are using a wirewound resistor in place of a speaker field, 1000 ohms will be fine. Personally, however, I feel 10 watts is a bit low. I prefer to use 25 watts minimum in these instances. You'll see why when that 10 watt resistor gets red hot!
I agree Ron, those 10 w wirewounds do get very warm!! Ive never seen one turn "red" yet. I have been using the 10 watters for smaller-space requirements for several yrs. I usually mount them across a good quality terminal-strip wherever they will fit on top of the chassis somewhere out of the way, and not to close to anything that the dissapating heat would damage. I have played my vintage radios for many,many hrs with no probs so far. I may have been "very lucky" so far also!! I will "up" the wattage to get a cooler-running resistor on this radio!! Thanks again for steering me in the right direction on these old radios!! I really appreciate all your help and pro advise very much!! Randal