Restored morrow mobile twins
Ii have just posted the restoration of my Morrow mobile Twins- MB-6 / MB-565 on my restoration site at:
last thumnail- lower right.
As can be seen in one of the photos- these were in very tough shape mechanically and had a number of intriguing electrical issues to be solved. I believe these to be the Cadillac of the mobile Twins both from a design and feature standpoint.
Sorry, if this post is a repeat. I tried to post earlier and it looks like it didn't 'take'.
There are those who think that the Gonset G-66B and G-77 are better!
However, the restoration looks excellent.
Very nice work, Dale! However, I think Pat/WA6MHZ will be more interested in your:
Originally Posted by W4OP
I restored the Gonset Twins for a friend many years ago Glen, and I am sure I have forgotten some details.
I would still pick the Morrow RX because:
1. Squelch (which could be very useful for mobile work)
2. Crystal calibrator with a separate dial calibration knob.
3. The field strength position which could also be very useful for tuning up a mobile antenna.
The Morrow TX would also be my pick:
1. The meter switch allows one to monitor Grid current, RF plate current, modulator plate current and modulator bias
2. Zero beat switch position- I don't recall the Gonset had this, but I may be mistaken.
3. The plate modulator is built in- wasn't it separate in the G-77?
The modulator in the Morrow uses a phase inverter to drive the P-P 6AU5's. I recall the Elmac interstage transformer as being a problem in that TX (AF-67). It need not be but was. I don't recall how Gonset did this.
I have long been a Gonset fan- particularly their hybrid 6 and 2M rigs- a little ahead of their time, but usable even today once you tame the IF.
VERY cool! IIRC, the Morrow Twins are the only ham radio gear that Morrow made. They decided to abandon the ham market, and just concentrate on aircraft radios and avionics.
Morrow also built 2 other units for amateur radio use:
The Model FTR, introduced in 1954, which was a receiver fixed tuned to 1525 kHz for use with the various mobile converters popular at the time (Gonset Super 6, Super 12, RME, etc.). This receiver included a BFO, r.f. stage, bandpass filters, "S" meter, etc.
The Model 5BRF mobile converter which covered 80, 40, 20, 15, and 11/10-meters. This was designed to be used with the FTR but could be used with basically any AM broadcast receiver.
Don't forget the predecessors to the Twins that I just restored the MBR-5 Receiver and an MB-560 Transmitter.
Also, The CM-1 Conelrad Monitor. Although not exactly a piece of ham gear, lots of hams owned one.
I basically considered all 3 of the "twins" series just to be a continuation of the same models. Besides the MB-565 transmitter and the MB-6 receiver, there were the MBR-5 and "Falcon" receivers, and the MB-560 and MB-560A transmitters. The "Falcon" receiver differed from the other receivers in that it had several i.f. bandwidths ranging from 2.8 kHz to 9.2 kHz. Also, the "Falcon" had separate broadcast band capabilities and had the Model BCT Conelrad monitor included. The "Falcon" was also available less the Conelrad monitor, but still with broadcast band tuner, for $19.55 less.
Very nice indeed Dale.
In the late 50's my mobile installation was a Gonset Tri Band converter and TBS-50D which was pretty low buck since I was still in HS.
Didnt go mobile again until at National where I had a NCX-3 and later a NCX-5 on loan 1963-69.
Havent been HF mobile since but if I did it would be those Morrows.
I must say, the Morrows do have a nice form factor- I was immediately attracted to them. I have casually looked at my 2nd set of the Twins and see some wires have been unsoldered in the RX, so this is going to be fun.
I restored an NCX-5 not too long ago. Except for the size, that would have been a wonderful mobile rig and stable as could be for the times.
Then again, cars back then had room for that rig.