Philco 89B won't oscillate!
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
From following the schematic, that tickler coil is open. It's supposed to be 5.2 ohms per schem. Nowhere to be found, although the others , well one reads 5.7 ohms. The other has a reading that looks to be charging a cap. Reading keeps on raising.
SM
(This post was last modified: 04-13-2016, 11:50 PM by Steve McDonald.)
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Time to pull the osc coil and rewind the feedback winding it's open.
Terry
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
O-coil pulled. Feedback winding is definitely open and not on the ends! The other 2 windings are okay. Anybody know what number magnet wire I'll need to rewind?And where to get the new wire?
SM
(This post was last modified: 04-14-2016, 02:55 PM by Steve McDonald.)
Posts: 16,219
Threads: 562
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Radio Shack. If it is still open in your place.
Internet. Ebay.
I usually just measure the diameter with calipers then determine the gauge. Then buy.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Original was 38g but it isn't real critical. Have used 32-38g with good result. As Mike said RS carries a pak of 3 or 4 different sizes in one pak.
Terry
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
I bought size 36, so this is going to be an adventure! I've never done this before! That wire is thinner than a hair! I broke it just trying to clean the wax off with naptha! The other 2 main windings measure 5.7 ohms and 5.0 ohms just as the schematic says. I'm in over my head, but I won't drown!
SM
Posts: 1,475
Threads: 69
Joined: Nov 2012
City: Kansas city, MO.
I'm pulling for you. You can do this. I have did two coils just take your time.
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
I have decided that I don't want to mess this O-coil up, so I've decided I will send it out to a competent rewinder. Anybody know anyone that will take this job?? If so, PM me and we will talk. Thanks in advance.
SM
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
Yup! A fellow from Canada helped me out and now, my 89B oscillates! Er, but it won't quit oscillating. Just one tone that rises in volume and note nearing the top numbers. And that is with all tube shields on. Anybody else ever hear of such a thing? But at least it's no longer silent! Fun, fun, FUN!
SM
Posts: 5,124
Threads: 271
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Steve, I merged your "89B Does oscillate" thread into your original 89B thread to keep the topic together.
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
I have been forced to pull the new oscillator coil- nothing but parasitic noise. Now, I'm nowhere with nowhere to go. I'm done.
SM
Posts: 5,124
Threads: 271
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
Steve, merged your new thread into the original 89B thread. Please see your PM.
Posts: 5,124
Threads: 271
Joined: Nov 2012
City: Wilsonville
State, Province, Country: OR
OK, just a thought here. The direction the coil is wound in is critical. If wrong direction is a possibility, try switching the leads and see if that helps.
Posts: 35
Threads: 7
Joined: Apr 2016
City: Medford, Oregon
I'll give that a shot. Thanks, Bob!
SM
Users browsing this thread: 2 Guest(s)
|
Recent Posts
|
B&K 1077B no video
|
I'm going to get back into it tonight. but I disconnected the 2 main resistors off this supply going to different parts ...TV MAN — 04:04 PM |
6TPZ and 5TPO Radio Help
|
Sorry. The test points are as follows:
1 - 0v
2 - 0v
3 - 0v
4 - 12v
5 - 0v
6 - 11.9v
7 - 12v
8 - 12v
9 - 12v...R3Sons — 02:09 PM |
6TPZ and 5TPO Radio Help
|
OK, so 18 and 19 as they should be.
What is "everything else?"
Try to be more specific in your descriptions:...morzh — 12:44 PM |
6TPZ and 5TPO Radio Help
|
Yeah, I'm still on 5TPO. Sorry, my bad, points 1 and 2 should be points 18 and 19 (easy mistake :think: ) X7 is shown ...R3Sons — 11:42 AM |
Philco 40-120C Filament Wiring
|
Hi folks, I'm in the process of restoring a Philco 40-120C and I'm finding the wiring to be a bit puzzling. According to...bluecap — 11:28 AM |
462ron
|
Hi Levi, here’s just a thought. Most radios run the oscillator higher than the dial setting. Say you set your radio to 1...462ron — 10:10 AM |
1930s Stewart-Warner Tombstone Radio need help identifying model number
|
Another Update: I found a couple of damaged coils inside this radio that might have something to do with why this radio ...captainclock1988 — 10:51 PM |
6TPZ and 5TPO Radio Help
|
If you are still on 5TPO, you lost me there. What X7? What Points 1 and 2?morzh — 08:37 PM |
6TPZ and 5TPO Radio Help
|
Quick progress report:
X7 is broken. Only one leg soldered, the other missing and the diode is cracked.
I've replaced...R3Sons — 05:05 PM |
6TPZ and 5TPO Radio Help
|
Oh...and you have electrolytic caps there.
All need to go and be replaced.morzh — 04:36 PM |
Who's Online
|
There are currently 3886 online users. [Complete List] » 1 Member(s) | 3885 Guest(s)
|
|
|
![>](https://philcoradio.com/phorum/images/bootbb/asb/right_arrow.png)
|