6-Tube Export Model Ch= 6Y60T or 6Y61T?

• alternative name: Chicago Radio Lab

Coverage:
SW 1: 2.2 - 7 MHz
SW 2: 7 - 22 MHz

The chassis in this model is with some certainty either 6Y60T or 6Y61T. We don't know the differences between the two. 

There exists another (export) radio with chassis 6Y61BT, which has a tag listing four possible chassis numbers: 6Y60T, 6Y61T, 6Y60BT, 6Y61BT (the B suffix denominating a switchable mains transformer 115/225 V).

Points of interest for this model:

• use of 6V6GT instead of 6K6GT of chassis 6Y61BT
• use of a cabinet similar to H725, G725 or K725 but then without handle
• 6Y61BT uses the same main speaker, but has two tweeters connected to the output transformer, the similar domestic version Y832 has two electrostatic tweeters
• the soldering lugs of this chassis' output transformer appear to indicate that additional wires were attached at some time
• the cut-out in the back panel seems to be ill-suited to reach the controls on the back of the chassis (radio-phono switch and RCA jack), partly due to the depth of the chassis
• we assume that originally a 6X4 was used

Those details cast some doubt on this receiver, it is possible that the chassis was placed into a bakelite case, losing the additional speakers in the process. On the other hand, domestic Zenith radios of the time were available with the same chassis in either cabinet design, so the situation is unclear for now.

In questo link sono elencati 4491 modelli, di cui 4096 con immagini e 3595 con schemi.
Elenco delle radio e altri apparecchi della Zenith Radio Corp.; Chicago, IL