Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 89B won't oscillate!
#16

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
#17

Time to pull the osc coil and rewind the feedback winding it's open.

Terry
#18

Sure is!

SM
#19

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
#20

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.
#21

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
#22

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
#23

 I'm pulling for you. You can do this. I have did two coils just take your time. Icon_thumbup
#24

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
#25

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! Icon_problem

SM
#26

Steve, I merged your "89B Does oscillate" thread into your original 89B thread to keep the topic together.
#27

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
#28

Steve, merged your new thread into the original 89B thread. Please see your PM.
#29

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.
#30

I'll give that a shot. Thanks, Bob!

SM




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM
Zenith H725
Ed; One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM
Zenith H725
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM
Zenith H725
The PSU filter cap arrived today (thank you USPS!) so I will work on that later. Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM
Philco 610B oscillator wiring
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM
The list of my radio & TV collection!
Magical chords of forgotten melodies, old nostalgic music on an old radio... Saturday night blues on the Mid-Waves on an...RadioSvit — 12:20 PM
Philco 42-345 Restoration/Repair
Thank you MrFixr55 the issue with this radio is that the internal coil antenna is missing and there was a wire in its pl...osanders0311 — 11:34 AM
Philco 610B oscillator wiring
Regarding the oscillator circuit which is comprised of the 6A7's cathode, control grid, and screen grid. These elements ...Radioroslyn — 10:33 AM
Philco 42-345 Restoration/Repair
Hi OSanders, First off, welcome to the Philco Phorum where Phine Phamily-Phriendly Pholks Phull of Philco Phacts and P...MrFixr55 — 08:41 AM

[-]
Who's Online
There are currently 2371 online users. [Complete List]
» 2 Member(s) | 2369 Guest(s)
AvatarAvatar

>