[jeffb]

Hello all, I am chugging along on my Philco model 19H- code 128. I am looking at the expected voltage chart from the Rider volume page 4-18. The Control grid to Kathode should be 2.2VDC- I am getting -21VDC. I think this may be due to me re-stuffing the triple electrolytic cap, item number 29. This has a 2, 8, and 10 uF cap in it. I think I have the 8 and 10 uF caps in correct, but there are no polarity markings on the schematic, so I put them in as they logically made sense. However, I did not put in an electrolytic in place of the 2uF cap. I put in a mica with no polarity(or something of a similar material, what I had lying around). Does anyone have any experience re-stuffing this electrolytic cap, and if so, should the 2uF cap be electrolytic, and the polarities? Thanks for any help.

[Ron Ramirez]

As long as the 2 uF you used has a high enough working voltage, then it will be OK.

Here's some notes.

If you were to use an electrolytic for the 2 uF section, the positive goes to the junction of the two 70K resistors, (27) and (28 ). Negative to the bottom of resistor (30) and on to B-.

Positive of the 8 uF section goes to the right side of resistor (49) (on the schematic) and on to the screen grid of the 42 output tube. Negative to B- (terminal 8 of the power transformer).

Now here's where it gets tricky. Chassis ground is positive in relation to B- in this set. Therefore, the positive of the 10 uF section (which only needs to be 50 WVDC) goes to chassis ground. Negative of the 10 uF section goes to B-.

One more thing. The voltage readings taken by the Philco factory in 1933 were done with voltmeters having an input impedance of 1000 ohms per volt. These crude old voltmeters loaded down the circuits under test, and all of those readings are actually inaccurate! Using today's modern DMMs, which have an input impedance of several megohms per volt, do not load down the circuit under test nearly as much, and provide much more accurate readings. All of this means that many (if not most) of the readings you take with your DMM will be higher than the published data.

[jeffb]

Hi Ron. Wow, that was fast! Well, here's my problem- I didn't know that the chassis ground is positive, so I have the 10uF cap in backwards. Second problem- I put the 2uF cap in, it has a WV of 250VDC. I think this is pushing it, since on the side where the two 70K ohm resistors met is 253 VDC, and the other side is a -21,8VDC. I thought that i would subtract the two and the differential is approx. 240v. Thanks so much for your help!!!

[jeffb]

Hello, has anyone run into this: part of the primary side of the oscillator transformer being open on the Philco model 19H, code 128? (Riders' volume page # 4-19). On the primary side, there is the usual primary winding, and also a small extra primary winding. On my radio, this extra small winding is open. The set now has lots of static but won't pick up any stations. I wonder if this will cause that, and would anyone know the expected value of this? Thanks for any help!!

[sam]

moved to same thread
Quote: Wrote:II. Multiple threads on the same subject not allowed.

When you start a thread, please keep the discussion within the same thread.

Example: "Philco 90 broken"

After you've started that thread, please do not start another thread on "Philco 90 bad resistor" if it is the same Philco 90 being discussed in the original thread. Give others a chance to respond to your questions rather than asking them again in a new thread - please be patient.

These sort of threads will be immediately deleted, to keep clutter to a minimum.

Please cooperate with me in keeping one thread in the same place rather than scattering it around.
sam

[jeffb]

Sorry Sam, I thought I did start a new thread with this. I must have added this to my other thread by accident.

[Ron Ramirez]

Hello, has anyone run into this: part of the primary side of the oscillator transformer being open on the Philco model 19H, code 128? (Riders' volume page # 4-19). On the primary side, there is the usual primary winding, and also a small extra primary winding. On my radio, this extra small winding is open.

Jeff - welcome to the wonderful world of Philco 89 and 19 sets.

Open tickler windings in oscillator coils is a very common problem with these sets.

Here is an older Phorum thread on this subject which should be helpful:
http://philcoradio.com/phorum/showthread.php?tid=8753

Do not forget to bake your coil as described in the link above. Seriously. These 89 and 19 sets need all the help they can get. The coils are known to absorb moisture over the decades, which can cause an otherwise good (or rewound) coil to prevent the circuit from oscillating as it should. Don't bake it any hotter than 200 degrees F.

[jeffb]

Hi Ron, again, thanks so much. So you call this a "tickler" winding? Also thanks for the other thread and all the help that is on your website. I will bake it in our oven at work very carefully. Take care!! I will let you know how I make out!

[jeffb]

Hello folks, I rewound this oscillator transformer "tickler" coil and the radio is now alive! BUT, there is a very weak signal. I am not sure if it is because it is in my basement workshop, I only have a piece of wire hanging off the thing for an antenna, but I was only able to get two stations in, barely, with my volume cranked up to max. I didn't align it yet. I will let you know once I poke around a bit and get some more progress, thanks!!

[codefox1]

Most of us get very week reception in the basement. You can try wrapping a couple of turns of insulated wire around your phone cable and connect to antenna terminal, or run a piece of insulated wire upstairs temporarily. But do align first.