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 89L-troubles
#31

Ok tried alignment.. Much better.. But noticed the Low end of band is very deaf..from about 600-900 Khz.. It is working since I can inject a signal from SG But levels is very high in order of -20 Dbm..Also noticed that if I put my finger on the RF tube it helps a lot.. Same thing on SW band Signal from Generator can hear but takes a higher signal..

Maybe weak RF tube? The Antenna coil checked out OK.. Not open..

Any clues??

Skip
#32

Quote Chas "What happen during the rewind of the Grunow was the removal of a cellulose acetate primary/secondary liner and replaced with thin plastic film. It was that liner than caused corrosion to the primary, the bottom layer.

I do not advocate placing an entire Philco chassis into an oven because a chassis may have coils wound with the cellulose plastic liner. Cellulose acetate is very flammable, that could be a disaster!"

Chas;
 You have the right thought except for one detail, cellulose acetate is NOT the volatile and flammable form of celluloid, it's it's much more dangerous cousin cellulose nitrate. Cellulose nitrate is the main ingredient in gun cotton, and was also used in the production of early motion picture film, which is chemically unstable like many other volatile substances. It was also used to make artificial silk, eyeglass frames, and billiard balls, until the dangers became obvious, such as two nitrate based billiard balls slamming together and exploding in flames. Cellulose is reacted with nitric acid in one, and acetic acid in the other, the nitric acid process isn't used in any cellulose based products anymore, except for some ping pong balls made in China, everything else, photographic film, acetate sheets, and rayon are made with the acetic acid process now, it is not volatile and does not go gummy and leach corrosive byproducts, nor explode into flames, though it will still burn if held to a flame.
Regards
Arran
#33

Arran, I have NO clue what you are talking about... Wrong thread?


Skip
#34

Arran is referring to Post #3 in this thread.
#35

Ok Didn't look back far enough.. Sorry about that..

Skip...
#36

Ok Everything was working fine..But now the OSC died.. I tried numerous 36 tubes all do not work now.. Even the one that did doesn't Oscillate now.. I was subbing tubes to see if I could get the low end of band to work better..

I hope Osc coil didn't open? I will check that tomorrow.. Then if OK.. Then Now what???

Skip
#37

Ok.. So radio did not Oscillate.. I put the original tubes back in and radio started to work again..Then on to my Volume problem  

I checked the Volume control and all the parts that connected to it..All were OK.. But this is what I found  Resistor 24 a 51K had came loose on one side  Not a great solder job by me.. I re-soldered the resistor and Guess what The Volume works.. All the way up.. Also the Radio now receives the lower end of band great..

Lesson:  Make sure I solder correctly and check connections after soldering..

I will do alignment over again just to make sure..

But seems all is well now..

Skip




Users browsing this thread:
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
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

[-]
Who's Online
There are currently 2348 online users. [Complete List]
» 1 Member(s) | 2347 Guest(s)
Avatar

>