Philco Flying Wedge 48-230
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
The power cord is wired to the same points, although I removed the tape and soldered the leads directly as there was enough cord left. The chassis is not hot but I'll double check polarized end.
I'll do another wiring and tube pin count check when I get home today and post again. The loctal bottoms are a bit tricky so I don't want to change anything until I'm sure.
Posts: 98
Threads: 2
Joined: Jul 2014
City: Eugene, OR
If they wired the power cord wrong it will cause problems. You have to do a bit more than just reverse the hot & neutral if you want to make the chassis "safe".
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
The power cord does present a safety issue, so does, for that matter, the whole AA5 radio idea, and absolutely do make it right, but in the meantime it does not affect the radio's operation.
Posts: 98
Threads: 2
Joined: Jul 2014
City: Eugene, OR
OK. I just mentioned it because The first time time I tried to wire one the other way I got it wrong and got symptoms a lot like he's describing. When I put it right the radio worked fine.
(This post was last modified: 07-23-2014, 12:51 PM by Squire.)
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
I have rewired the switch on another unit where it needed a new cord and know how to do that. I usually leave things as original as possible but they can be dangerous and I know when it's plugged in it's not hot if the switch is off. Switch on hot I'm not sure about. I'll have to check which side goes where later. I'm not sure how this would affect the audio if it was wired to the opposite side of the plug.
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Just buzz the wider prong to chassis when the switch is ON.
It does help better reception to have chassis on N as N in essence is Ground in 110V system.
They had non-polarized plugs before. Sometimes when having noisy reception reversing the plug helped, but there would be, neverthelrss, reception, as for RF purposes L is grounded.
(This post was last modified: 07-23-2014, 01:19 PM by morzh.)
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
morzh,
Transformer (#29, not 33) goes to pins 3 & 4, A5 to pin 4, A6 to pin 6 ..which tube are you talking about? 7A8, right?
What about that center wire coming off the post of the tuner that's going to pin 5 of the tube 50A5?
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
You meant 33, not 29? (you have it backwards). Yes 7a8.
The pin 5 of the 50A5 is a no-connect pin, it is used as a binding post.
This is the way the sch is, you said pins 4 and 6 are swapped in your case.
(This post was last modified: 07-23-2014, 04:21 PM by morzh.)
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
Looking at the pictures with numbers given to parts on the service sheet it shows 33 as the speaker transformer and 29 is the oscillator coil.
The antenna loop has a connection to A5 lug, and the other is on the top connector which goes to pin 5 of the 50A5 tube, which then connects to pin 5 of 14B6. Is that correct?
(This post was last modified: 07-23-2014, 08:31 PM by mikeyhitchfan.)
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
http://philcoradio.com/phorum/attachment.php?aid=5066
The link from the page 1 of this thread.
Look at the sch and the chassis picture.
Always go by the sch. Do not go by anything other than the schematic. It screws up communication, complicates life and spoils karma.
(This post was last modified: 07-23-2014, 09:11 PM by morzh.)
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
OK, I swapped the 2 7A8 connections from the bottom of tuning condenser. No change. What 2 points should the loop antenna be connected to? Still not sure it's right.
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Look at the sch. Item 32 (a square) is the loop.
Connected to the cap #12 with one end, and to the tuning cap and the 7A8 pin 6 with the other end.
On your photo I do not see the loop. I hope as you said before it is connected.
(This post was last modified: 07-23-2014, 09:46 PM by morzh.)
Posts: 4,682
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
These sets, as well as all other Philco AC/DC or transformerless power supply designs, have the common negative isolated from the chassis, they are NOT hot chassis sets. They chained all of the B- points together with a bus wire and then coupled the chassis to the B- with a capacitor-choke assembly and a resistor. It does not make it 100% safe but still much better then having the power line soldered directly to the chassis.
I've seen the polarized plug idea circulating for a few years and believe that it gives a false sense of security. For one thing how do you know that the outlet is connected correctly? For another even with the polarized plug that will only work if the set if on, if it's off you will find that it still gives a tingle if you rub your knuckle on the chassis.
The shock hazard was not unknown even when these were new, there were warnings with all of the literature about connecting a ground, and steps were taken to prevent someone from touching the chassis itself such as having a back and plastic knobs. In fact some Philco Transitone sets originally had rubber covers to insulate the chassis screws.
There are two ways to make an AC/DC sets 100% safe, treat it with respect, or operate it through a GFI outlet or an isolation transformer.
Regards
Arran
Posts: 34
Threads: 2
Joined: Jul 2014
City: Costa Mesa CA
So if I ignore the pictures and look at the schematic...A5 goes to pin 4 & A6 goes to pin 6 (of the 7A8 tube), right? Now, in the photo it shows A5 as the one with the ground lead connected to chassis, and it shows A6 as the other side, right? Well, this is why I'm confused. The schematic is the opposite if the way it's wired. The 47mmf cap (#15) comes from A6 side (not A5) connects to the osc coil then to the #15 cap then to pin 4. So, is it possible that the schematic has A5 & A6 labeling reversed in error? This is why this radio is proving difficult to diagnose. A sig gen would be most helpful.
(This post was last modified: 07-24-2014, 09:05 AM by mikeyhitchfan.)
Posts: 15,691
Threads: 551
Joined: Oct 2011
City: Jackson, NJ
Mikey
I cannot honestly figure out the photo. If you did several prosectives or red-arrowed the parts you referred to....
But the sch shows correct arrangement: the feedback coil 33 goes to the 1st and 2nd grids which is the oscilator arrangement with pentagrids and octodes, and antenna (in other radios - antenna transformer or coil) goes to pin 6 which is the control grid of the amplifying portion.
And, yes, a sig gen is a must for anyone who is half serios about fixing old radios.
And it s cheap.
(This post was last modified: 07-24-2014, 09:42 AM by morzh.)
Users browsing this thread: 1 Guest(s)
|
Recent Posts
|
Jackson 715 not working
|
Mrfixr55, its working now. I cleaned the switches and sockets with spray cleaner. Thanks for helping on this one.daveone23 — 06:26 PM |
Jackson 715 not working
|
Now that you posted the schematic, I don't know why that Sprague electrolytic cap is across the meter, as it is not indi...MrFixr55 — 05:51 PM |
HiFi (Chifi) tube amp build - but my own design.
|
What may be lacking in the PP Tube amps may be the 2nd harmonics, which some, especially RCA back in the day called &quo...MrFixr55 — 05:32 PM |
Jackson 715 not working
|
Usually in an emission tester, the tube under test is measured as if it were a diode. So, some testers connect all the g...RodB — 04:17 PM |
Restoring Philco 37-604C
|
Yep. F5 is green, D5 is Red.
Red is Bad.
Green is Clean.morzh — 01:30 PM |
Jackson 715 not working
|
I did start to do that but I stalled out because I could not figure out how the grid and plate get voltage. In this diag...daveone23 — 11:52 AM |
Restoring Philco 37-604C
|
(Insert Homer Simpson "DOPF" Here.)
When all fails, look at the can. Took the Ron Ramirez advice, red Caig D...MrFixr55 — 09:23 AM |
Philco 91 Speaker Replacement
|
From your text I am not sure if you intend to use the existing speaker with a resistor instead of the field coil.
It wo...morzh — 08:44 AM |
Philco 91 Speaker Replacement
|
My field coil is bad. I am still hoping to find an original, but if I can't I will go with a fitting Philco speaker, 125...dconant — 08:34 AM |
Philco 91 Speaker Replacement
|
As Rod said, it is OK to use a fitting speaker, and then look for an original one.
If you buy a Hammond 125 output tr...morzh — 08:15 AM |
Who's Online
|
There are currently 3930 online users. [Complete List] » 1 Member(s) | 3929 Guest(s)
|
|
|
|