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

Rf transformer replacement
#1

Hello, I am working on an aa5 that is missing one of the rf transformers, the original should measure 16/16 ohms but the closest I have found measures 17/19 ohms would I be able to align the replacement to work? If not, can a capacitor be added across the coils to tune in the correct freq.? Thanks, Todd
#2

What model and what year?
Regards
Arran
#3

52-542
#4

I guess you mean IF transformer? No RF xfmrs in that set.

The first IF is pretty generic. Note that the second one has the 'scrubber' components (R6+ two caps) mounted inside the xfmr. That's common too in 1950s sets but note that it is not your standard 4 connection can.

You can mount the R6 and two disc caps (100-150pf) externally if need be.

Otherwise, don't be concerned over the DC resistance of the coils. That has no impact on the circuit. If your replacement is of the same general type from that era you can pretty much count on it being the same frequency (455kc).
#5

Yes, I-f. So as long as it is a 455 can the resistance no matter how high or low is not a factor? Also I added the 2-120pf and resistor as in the schematic. Now I can adjust it in at 455 with my sig. Gen. But when I try to adjust the 1500/1600 on the tuning cap through the loop ant. as per alignment data. The only way I can pick up the sig gen is at the lowest end (fully meshed) no matter what freq is on the gen. Would polarity be an issue? The dot is always no.1 terminal right?




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Hickok AC51 tube tester
Note that no power cord, power switch, or power transformer switch are shown. That (along with my experience with full s...DaleHCook — 07:09 AM
IF can wire size and Rubber mounts?
A pair of wire strippers can give you an idea of what the existing gauge of the wire leads are in the IF can, I think it...Arran — 06:07 AM
My last cabinet for this year
Hello Dan, That is really beautiful what great looking radio you have ! I have friends who live in Calgary and the wea...radiorich — 01:51 AM
Philco Predicta Siesta picture over time getting dimmer
I found that the wire insulation was burnt.  The fly back needs corona dope! Why would someone put that there?Platinumblonde36 — 01:09 AM
Philco Predicta Siesta picture over time getting dimmer
This is what it looked like beforePlatinumblonde36 — 01:01 AM
Philco Predicta Siesta picture over time getting dimmer
Platinumblonde36 — 12:58 AM
Philco Predicta Siesta picture over time getting dimmer
Platinumblonde36 — 12:57 AM
Philco Predicta Siesta picture over time getting dimmer
I'm finding some strange things in my set and for the most part it's also original, so I need to start going over everyt...Platinumblonde36 — 12:55 AM
12' Philco
Not anymore Mike. Andre The Giant Born: May 19, 1946, Coulommiers, France Died: Jan 28, 1993 (46 years), Paris, Fran...RodB — 11:53 PM
IF can wire size and Rubber mounts?
Renovated Radios do carry what you need. As for the voltage, a wire should be at least 300V-rated.morzh — 11:13 PM

[-]
Who's Online
There are currently 3937 online users. [Complete List]
» 2 Member(s) | 3935 Guest(s)
AvatarAvatar

>