Model 20 speaker or model 70 ?

Register

Guest Join Us

Hello Guest,

Please feel free to join us!
There are many more parts of the Phorum that only members can see.

Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Rating:

0 Vote(s) - 0 Average
1
2
3
4
5

Linear Mode

Model 20 speaker or model 70 ?

Ron Ramirez
Silent Key

Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand State, Province, Country: Indiana

#7

12-08-2007, 04:23 PM

The primary impedance of the original output transformer was 6700 ohms per Philco data; secondary impedance 0.7 ohm.

Using these figures...the closest match you are going to get will be by connecting the speaker voice coil leads to either terminals 1 and 3 or 5 and 6.

Universal audio transformers do not offer exact matching of output to speaker voice coil; instead, they offer "close enough" matching to enable their use in many different radio receivers.

These transformers have six terminals for the secondary connection to your speaker voice coil. You will use the two terminals that most closely match the output load impedance to your speaker voice coil impedance.

Use whichever combination sounds the loudest and best: Terminals 1 and 3, or 5 and 6.

--
Ron Ramirez
Ferdinand IN

Find

« Next Oldest | Next Newest »

Messages In This Thread

Model 20 speaker or model 70 ? - by Danny - 12-01-2007, 10:27 AM

[No subject] - by Ron Ramirez - 12-01-2007, 11:01 AM

[No subject] - by Steve Davis - 12-01-2007, 11:02 AM

[No subject] - by Danny - 12-01-2007, 01:02 PM

[No subject] - by Ron Ramirez - 12-02-2007, 12:37 AM

[No subject] - by Danny - 12-08-2007, 02:09 PM

[No subject] - by Ron Ramirez - 12-08-2007, 04:23 PM

[No subject] - by Danny - 12-09-2007, 04:27 PM

View a Printable Version

Users browsing this thread: 1 Guest(s)

Recent Posts
Philco 42-345 Restoration/Repair
Hi OSanders, Look carefully at the band switch. Turn it slowly and "wiggle" it around the desired band. ...MrFixr55 — 12:33 AM
5U4 vs 5Z4 tubes
I think that RCA and GE introduced metal tubes in the USA in 1936. I don't know if they were being made by RCA, GE or b...MrFixr55 — 11:20 PM
Philco 42-345 Restoration/Repair
Vlad95, Thank you for the stringing guides and wow there are so manyosanders0311 — 06:01 PM
5U4 vs 5Z4 tubes
A pre war Hallicrafters, and an early one too, very nice! 1936 is pretty early for metal tubes too, which would explain ...Arran — 05:58 PM
Philco 42-345 Restoration/Repair
Thanks Rod, "When you hear the background hiss and no station it usually indicates that the oscillator quit" ...osanders0311 — 05:52 PM
Philco 42-345 Restoration/Repair
RodB :beerchug:Vlad95 — 10:22 AM
Philco 42-345 Restoration/Repair
Vlad, you nailed it. Swiss and German roots.RodB — 09:54 AM
5U4 vs 5Z4 tubes
Well this is a Hallicrafters SX/9 circa 1936. No real issues so far although I dodged a real bullet with a cap that was...bridkarl — 07:59 AM
5U4 vs 5Z4 tubes
The pinout is the same but the 5U4 has a 3 amp filament, verses 2 amps or less on the 5Z4. I think that the pinout of a ...Arran — 12:04 AM
Philco 42-345 Restoration/Repair
By the way. osanders0311 Take a look here: Dial cord stringing Guides May be here you can fount correct string settin...Vlad95 — 11:15 PM

Who's Online
There are currently no members online.