EH Scott Radio Enthusiasts

The Fine Things are Always Hand Made

At some point will need to purchase a pair of tweeters for my Allwave 23.  MIght anyone know what the ohm readings might be on each driver?  Would like to make sure that is correct before I commit to a purchase. 

Thanks in advance. 

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Not sure what you are asking.

If you are seeking a substitute for the Scott AW-23 tweeter set, 16 ohm each will suffice, wired in series and in series with a 2 MFD cap of about 600 volts or more, also in series to allow only higher frequencies. The cable  plug is the larger 5 pin style plug that fits the sockets on the pedestal speaker - but refer to the instruction manual for installation with regard to the short cable plug on that speaker. Be careful.

However, the big issue is the Scott AW-23 optional tweeters have field cols. The tweeter field coils substitute for the big tapped power resistor in the base of the AW-23 pedestal speaker. The two tweeters have different field coil arrangements. Carefully study the AW-23 circuit diagram for amp and speaker to grasp the wiring with and without the optional Scott tweeters.

The correct Scott tweeter pair of tweeters (with wiring harness) uses Q series 5 inch  Jensens but having E H  Scott decals. Again - field coil tweeters, not the permanent magnet type used later for the Scott Philharmonic, nor the even later tweeters for the optional high fidelity speaker system of 1940-41.

To add to confusion, the tweeter set for the 1935 earlier 5 knob AW-23 and for the 1936-37 later 7 knob Scott 23 tube radio are different (use different Q series tweeters).

a Scott tweeter set for the 1936-37  Scott 7 knob AW-23 is on eBay now. Note has field coils and harness.

eBay item number:
124210051164
Study the photos and description. Seller is asking a steep price. But listing is informational.

Thank you for the reply, there seems to be two sets available on ebay.  Don't want to pay quite that much, may try to make an offer? 

If you could check out the other set available would be appreciated to make sure compatibility with my 7 knob 23?  For that price while they seem to be ok, they have not been checked with an ohmmeter so they might be doa?  Thanks   

Other pair are for sale by antique_radio.  thank you

The 7 knob AW-23 of 1936-37 should have the later version pedestal speaker, which should have the 19 ohm voice coil Pedestal 12 inch  speaker (a special version Magnavox). 

The correct tweeter pair are Q series  8685A and 8686A.  One of them has a tapped field coil.

Both tweeters sets on eBay I saw are the later version for the 1936-37 AW-23.

One tweeter has a 2 MFD cap, which should be replace with a modern cap of 500 volts or more.

(The pair for a 5 knob AW-23 of 1935 have lower tweeter model numbers, and the main speaker a 38 ohm voice coil)

Thank you, will try to measure the voice coil tomorrow on the pedestal to make sure which woofer this is. 

Measuring at the voice coil I get 4 ohms, but as they are connected to other items may be a false reading?  Should I try to take a reading someplace other than the two silver wires coming off the voice coil?

Thanks

We have had this discussion before.  There are two versions of the tweeters differing only in the plugs and sockets on the tweeters.  Electrically they are the same.  Either set of tweeters will work with either version of woofer.

The voice coil must be separated from the output transformer to obtain a correct DC resistance reading of the voice coil.

Norman

That is what I thought.  So if either one will work, might try to make a deal, don't know if they will go low enough to fit my budget, but may give it a try.  Thanks so very much for your time. 

Norman - now I recall you comment from a couple years ago or so:  early and late  tweeters same electrically. 

Todd - Voice coil impedance of 38 ohms is not the same as the measured resistance with a meter, which be about  31 ohms. 19 ohm impedance voice coil will measure about 15 ohms with a meter.

Thank you, as long as there is some impedance the woofer should be working regardless of value.  So at this point don't want to unsold er any driver connections as long as either sets of tweeters will work with the woofer and system. 

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