Posts: 22
Threads: 6
Joined: Dec 2015
City: Hamilton, ON, CA
Hello MrFixr55 thanks so much for the input , what I am going to do is change every capacitor in this set and also every resistor , for the resistors I have ordered 2 watt for all of them except for the long wire wound resistor #6 and #7 that had the jumper across it I have ordered a 1K 10 watt like you told me , I did take off the jumper and tested the #6 and #7 tabs and I got 975 ohms , I have no idea why the jumper was put in , I was thinking that. Maybe when the set warms up that section opens with the heat expansion? , so I thought I would disconnect that section and install the new 1K 10 watt resistor , I have not and won’t power up the set until I change all the parts don’t want any undo problems , this is the first set I have seen or or worked on that has two output transformers , oh well hope both are ok again fellows thanks for the input and help all the very best Rick
Posts: 1,409
Threads: 72
Joined: Oct 2007
City: Linn Creek, MO
Rick,
There should be only one output transformer, it should be mounted on the speaker. If there are two, someone has made some sort of crazy modification.
Steve
M R Radios C M Tubes
Posts: 16,441
Threads: 573
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
I am pretty sure Rick means the interstage and the output xfmrs.
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: 22
Threads: 6
Joined: Dec 2015
City: Hamilton, ON, CA
Sorry fellows for the mix up , when I look at the parts list and schematic I see part #21 is a push pull Input transformer and #28 is a Push pull Output transformer also there is part #27 with only two wires on it this is a filter Choke , when I looked at the two push pull transformers they had three wires on one side and two on the other side on both , I just thought that most push pull output transformers I have worked on look this way , I am wrong never seen a radio that had two transformers that both looked like output transformers , oh well learn as I go and thanks for the lesson , you are right this set has the output transformer mounted on the speaker ,this set is a floor model not a cathedral, low boy style, thanks again all the very best Rick
Posts: 16,441
Threads: 573
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
The interstage transformer has to take some serious current, 3-5mA, which is not a small thing considering the signal amplitude. So they are size of output transformer, in 20, in the 86 - 112 radios, same thing.
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.
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
Zenith H725
|
Arran - thanks, I'll chase those easier things first. The sockets and pins were dirty, and there was a bit of crackling ...EdHolland — 11:49 AM |
38-690 Gill Cloth
|
The 37 and 38-690 use the Philco ribbed cloth; Michael Katz sells a nice reproduction of it.Brad Winder — 09:06 AM |
philco 91 detector transformer
|
thank youmg34.42 — 12:15 AM |
Zenith H725
|
Ed;
Before getting into the IF cans I try to make sure that the tube sockets, and tube pins are clean, those 7 and 9 p...Arran — 11:42 PM |
Zenith H725
|
Well something isn't right, there's a lot of crackling, particularly on AM, but it seems also to affect FM to an extent....EdHolland — 10:46 PM |
Zenith H725
|
Hello Ed,
That is wonderful news and far as dim bulb tester I need to build a new one .
You, are lucky that nothing g...radiorich — 10:33 PM |
Zenith H725
|
Cap replacement is completed. (Excepting PSU filters for now). A cautious power up got the expected behaviour of the dim...EdHolland — 06:56 PM |
Philco model #20
|
The interstage transformer has to take some serious current, 3-5mA, which is not a small thing considering the signal am...morzh — 06:19 PM |
Philco model #20
|
Sorry fellows for the mix up , when I look at the parts list and schematic I see part #21 is a push pull Input transform...onlyrick — 03:34 PM |
Zenith H725
|
Lunchtime today brings me to about 1/4 through the paper cap replacements, starting at the RF end. Everything seems to b...EdHolland — 02:44 PM |
Who's Online
|
There are currently 870 online users. [Complete List] » 2 Member(s) | 868 Guest(s)
|
|
|

|