Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
I just finished re-stuffing the e-caps, and a couple Bakelite blocks that were noticeably shot. After that I powered up the set with all the tubes expect the 5Z3 rectifier. All went well so I powered up again with the rectifier in place and the set came alive -sort of-. I got some buzzing and whistling from the speaker. Made me feel better that the set wasn't deaf. Now to finish recapping the set before the next power up.
During the full power up the Shadow meter even seemed to function. I could see the vane moving with the sound coming from the speaker.
(This post was last modified: 04-04-2013, 12:04 PM by ipwizard.)
Posts: 16,507
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Nice....I hope the pleasure is proportional to the chassis's size 
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
busy re-capping today, and I come across a cap #40 on the schematic. It's value is .00125uf (1250pf). The replacement I have for it is .00150 (1500pf) will this be ok. I'm not sure if its critical to get the value of this cap as close as possible.
[Image: http://i1129.photobucket.com/albums/m501...bfebeb.jpg]
Thanks
(This post was last modified: 04-05-2013, 12:27 AM by ipwizard.)
Posts: 16,507
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
I think here it is OK to use 1.5nF.
Posts: 7,301
Threads: 269
Joined: Dec 2009
City: Roslyn Pa
Hey Mike,
Your going foreign on us again!!!! NF
We got to get together sometime
soon my friend.
Terry
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
Quote:I think here it is OK to use 1.5nF.
Thank, ill use what I have and hope for the best.
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
I agree with Morzh, I don't think it will hurt. Let us know how it goes.
--
Ron Ramirez
Ferdinand IN
Posts: 7,301
Threads: 269
Joined: Dec 2009
City: Roslyn Pa
Worst case the osc won't run or it may shift the frequency a little. If it is running I wouldn't lose any sleep over it. Just reset the fq
Terry
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
Probably .001 mfd would work just fine. Need to do an alignment anyway when you get done recapping and recarbing the set.
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
Thanks all. Hopefully I will be mostly done with all the re-capping this weekend. I have found a lot of resistors that are way out of spec (+-20%) in this set. So they are getting replaced as I re-cap.
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
Finished the recapping last night. Powered up and it sings. The tone switch has something funky going on with it though. When moving the tone switch the sound will squeal, and pop and carry on until you get it just right. I sprayed it and the band switch with deoxit and let it sit over night we'll see if that made a difference tonight.
I have to say from the few minutes I had the set playing that it is a very sensitive set. I suspect it will be a very good performer after an alignment.
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
Tone control issue.
In two of the positions the tone control works as it should, in the other two positions the sound will squeal, high high pitch. There are two 4meg resistors that are measuring 5.2meg. Im going to swap these for 3.9meg.
Anyone have any idea what I should check? I have replaced all the caps with the proper values except the mica's.
[Image: http://i1129.photobucket.com/albums/m501...b33490.jpg]
Thanks
(This post was last modified: 04-15-2013, 05:26 PM by ipwizard.)
Posts: 1,114
Threads: 14
Joined: Feb 2013
City: Irvington, NY
I would not be too concerned about replacing the 4 meg resistors. There only purpose is to act as bleeders for the tone control caps (.01 uF and 3000pF) and their value is not critical. They prevent any leakage from building up a charge on the caps and causing a pop noise when the tone control is rotated which grounds the cap in that switch position.
Do you have a tube shield on the 77 first audio tube? It is right next to one of the output tubes and the grid cap lead is very sensitive to stray signal pickup. The grid cap lead should be inside the tube shield. Had the same type of squealing problem with a model 610 where the 75 audio stage is right next to the 42 output tube. Putting a shield on the tube with the grid lead inside cured the problem.
Posts: 7,301
Threads: 269
Joined: Dec 2009
City: Roslyn Pa
When you get it playing properly I'm curious how well it works?? I just picked up one and a half 116X myself. Haven't had a chance to go though it but it looks to be a really outstanding set be looking at the diagram. It one has been serviced but I'm not sure if it is going to need some more going over. So now I have 116X, 37-116X code 121 and a 37-116X code 122. Think I'm going to have to sell some sets as I'm running out of room. It's great fun!!!! I think I hear that the 37-116 is a better sounding set than the 38-116. I think I'll stop with these three although I would like to get a 680.
Terry
Posts: 335
Threads: 50
Joined: Apr 2011
City: Apple Creek
State, Province, Country: Ohio
Quote:Do you have a tube shield on the 77 first audio tube? It is right next to one of the output tubes and the grid cap lead is very sensitive to stray signal pickup. The grid cap lead should be inside the tube shield. Had the same type of squealing problem with a model 610 where the 75 audio stage is right next to the 42 output tube. Putting a shield on the tube with the grid lead inside cured the problem.
That was the issue. i put all the tube shields on and that fixed the tone control issue along with the "birdies" while tuning. many thanks!
Users browsing this thread:
|
|
Recent Posts
|
|
PT 6 chassis screws size???
|
| Hello bridKarl,
that sounds right or maybe 8/32 .
Sincerely Richardradiorich — 01:00 AM |
|
PT 6 chassis screws size???
|
| Have this done except for missing chassis screws.
It looks like 1 inch 6/32 sheet metal screw may work but can anyone s...bridkarl — 10:32 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Hello Stormlord,
Well done on rewinding that coil it turned fairly good for your first one.
Sincerely Richardradiorich — 09:12 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Well here it is. It ain't pretty, but hopefully it'll work.
I checked it with my DMM on continuity and it keeps and r...Stormlord5500 — 08:56 PM |
|
Philco 42-345 Restoration/Repair
|
| Yes, 57 is an electrolytic cap that should be 12 mfd 400 volts according to the parts list from the Phorum library schem...RodB — 06:01 PM |
|
Philco 42-345 Restoration/Repair
|
| Looks like if I am reading it correctly it looks like the silver capacitor#57 that appears to be a replacement is of a l...osanders0311 — 05:09 PM |
|
Philco model 38 code 121 not receiving signal.
|
| Thanks Arran. Yeah this plastic is pretty thin. It's a little thinner than the original stuff. It kinda reminds me of p...Stormlord5500 — 04:37 PM |
|
Testing a speaker and output transformer Trutone A2-G
|
| The equivalent of one short turn is basically the same as that of a shorted load.
If it is the primary's turn, then the ...morzh — 03:53 PM |
|
Testing a speaker and output transformer Trutone A2-G
|
| I've never had an output transformer become shorted, the failure mode is usually an open primary, or in a center tapped ...Arran — 03:52 PM |
|
Philco model 38 code 121 not receiving signal.
|
| As long as the plastic sheeting isn't too thick, I think that the thickness of photographic film would be just about rig...Arran — 03:19 PM |
|
Who's Online
|
| There are currently no members online. |
|
 
|
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
