Motorola Model 57R NEW OLD STOCK (NOS) Doesn't Get Any Better Than This!
It doesn't get any better than this folks.
In the world of collectibles, these three letters are music to the most discriminating collector; 'NOS.' New Old Stock, baby! This means vintage period piece that is brand new!
I come across anything NOS very infrequently. The last NOS piece I had was also a Motorola, and it's high on my list of "wish never sold it."
Here is the one I still pine over. I've had a few other NOS pieces. They are not only exceedingly rare and difficult to find, but expensive to buy.
This NOS Motorola turquoise cabinet came in its original Motorola factory box with labels. The cabinet was impeccable. This model cabinet is especially prone to heat cracks. Moreover, the circuit board is one of the more difficult ones to repair and trouble shoot. More on this later.
Here is the nice original shipping carton.
This pristine turquoise cabinet spent the last 60 years inside this box without electronic guts installed until today.
I have been savoring the opportunity to finally put this radio together using the best parts from donor radios. Until this afternoon, not a screw hole on the cabinet has ever been fitted with a screw.
The turquoise color is as it would have been back in 1957 when Motorola manufactured it! Because of its lack of exposure to ultraviolet light, the turquoise is textbook sample and important for historical reasons.
See what I mean?
Building this radio is one of the biggest joys I experience in this hobby of mine. This NOS cabinet has been sitting around my shop for over a year while I collected the best parts from donor 57Rs. Today was the day I decided I would finally give new life to this original pristine piece.
First, let's go over the ordeal to acquire parts from donors. This particular model uses special propeller type knobs. In order to get the right color knobs to match this turquoise model 57R, I had to buy another Motorola Model 57R in turquoise! These days, this particular design is getting harder and harder to find, at any price.
Here's a picture of the donor turquoise Motorola 57R. Notice the heat crack on the top. The donor 57R is definitely a little lighter shade of turquoise and a little less green. Hard to tell in the photo but apparent in person.
Here are the knobs I needed from the parts 57R for Mr NOS:
What happens to the rest of parts 57R you ask? At Retro Radio Farm, we believe in reuse and recycling everything. This 57R with crack may be repaired and repainted and resold. The difficulty will be the knobs but I think I have an extra set of white propeller knobs lying around.
The circuit board from the donor 57R was in good shape and actually worked great! For some reason, these 57Rs are a challenge to repair even more so than other Motorolas with Placir (double sided) circuit boards or maybe I've just had bad luck. Perhaps it's the wide expanse of unsupported circuit board between the internal bottom mounts that causes failure due to weight of the components over time. It makes troubleshooting the circuit a nightmare. I've had to repair cracks in these 57R circuit boards. I've seen extreme concave bows in the boards due to flexing and weight. The interconnects between one side of the circuit get disconnected to the other side and it's not visible to the naked eye. Ouch!
This one was straight and no breaks!
What's more it sounded great after I replaced a blown speaker that came from a pink 57R donor.
A few tubes were weak and needed to be replaced:
I decided not to replace the old capacitors because there was not discernible hum and I like to keep things as original as possible whenever I can.
There was one 27 ohm that measured 38 ohm. See the blue resistor on the left in the photo below.
The turquoise donor 57R did not come with an antenna so I had to steal one from a black 57R I had on hand. These antennas are specific to Motorola 57Rs from the late fifties. They are mounted with a plastic cover on to the backing board. Many of these 57Rs antennas broke off over the years.
Here the antenna from the black 57R donor mounted to the backing board of the turquoise 57R donor:
The cord came from the turquoise 57R donor. I decided to zip tie the cord to the backing board to reduce fatigue at the interconnect.
Here's what the radio sounded like after I cobbled together all the best parts from turquoise, pink, and black donor 57Rs.
Here are some pictures of the turquoise 57R cabinet just before assembly - for the first time!
After a thorough voltage test at various points in the circuit and burn in period, I decided it was time to assemble the components. Here's with the components inserted into the cabinet after the circuit board and components were detailed.
To avoid heat cracks in the pristine cabinet, I fashioned a heat shield made out of cardboard and aluminum foil. This should work just fine in distributing the heat from the amplifier tube. Back in the day, many manufacturers used the same materials for heat shielding. Unfortunately, Motorola was not one of them.
Here's what it sounds like fully assembled
Not sure if I want to sell this because I know I will regret it.