CU's console ratings

[Firedome]

Here's CU ratings for mid-level consoles, I think about 1964. I believe some may have been tube models but some brands transitioned to SS earlier than others. The FIsher Philharmonic IV P-290W (walnut) still has a all-tube chassis, but others may have been SS or hybrid by now. It'd be interesting to know what years the major makers went to SS. Fisher varied model by model but tended to be a bit later than most. Oddly, unlike Scott, they used Germanium transistors at first. These are listed in ratings order from their test results. A mid-level model typically ran in the 350 to 400 range + or -.

[Motorola minion]

The Zenith in that list is a 1965 model, possibly with just a solid state amp and tube tuner/preamp.

I know GE, Fisher, RCA, Packard Bell and Zenith had solid state designs for amplifiers first then transistor based preamp/tuners a year or two later. RCA made a decent enough germanium transistor, not good enough for some like HH Scott who went with silicon transistors.

Magnavox went total solid state before the others, starting with 1963 or 64 models. The RCA transistors they used in their consoles before even RCA did! Motorola went all SS later for some reason, most 1964 models I have seen are all tube. That always surprised me because Batwings were symbolic of solid state, making 2-way communications history

Admiral, Sylvania and Philco had solid state designs starting with 1965 models. Many TV-radio-phono combos were made by these three, but their TOTL electronics was found only in a big console. I have a 1966 Admiral combo whose SS receiver uses Texas Instruments silicon transistors.

Cannot speak for Sears and Airline but I would avoid those SS unless they used RCA or other reputable transistors.

[Firedome]

Quite a mixed bag of tube and hybrid and SS electronics for those models then! Thanks for that info Dave!

[electra225]

Magnavox introduced their Astro-Sonic line of solid state instruments for the 1963 model year, along with holdover all tube models, often in similar cabinets. Magnavox never made a hybrid stereo console chassis.

[Firedome]

Fisher made hybrid consoles with tuner-preamp tube chassis with SS amp outboard stages through about '67, possibly later even, a wise thing probably as their Nuvistor tube/all-tube front ends and preamps were truly exceptional performers.

[TC Chris]

One of my curbside finds was a Fisher 600T, transistor except for the Nuvistor front end. Before I knew what was under the hood, I plugged it in to see if it made noise and was disappointed to hear nothing on FM. But as I fiddled with switches and buttons, it started hissing at me and I could tune in stations. Then I pulled the lid and saw the Nuvistors and understood what had happened. They may be Nu devices but they still need to warm up before they start conducting. And I'm wondering if Nuvistors have some sort of controlled warm-up to make the heaters last longer.

Chris Campbell

[Firedome]

My understanding is that Nuvistors actually ARE a vacuum tube, designed to be small enough to compete size-wise with transistors, sort of a last gasp... they even sort of look like one! The good thing is that they worked very well for their intended use in FM front-ends where Fisher in particular was a big proponent of incorporating them in their designs to great success.

When RCA introduced them they actually concomitantly re-named their TV line around 1959/1960 "New Vista" as a cross promotion for their new technological advance.

[TC Chris]

Yeah, they are tiny high-tech vacuum tubes, and apparently especially well-suited to small-signal work like RF circuits in receiving gear. The benefits of tubes without all the heat and excess power consumption. Having your cake and eating it too....

Chris Campbell

[Motorola minion]

If you compare data sheets RCA Nuvistor's 6DS4 and 6CW4 with 6HA5, it may reveal how close in spec they are. Particular attention paid to pf values (inter-electrode capacitance) will reveal clues. Older types 6CY5, 6GK5 will likely be higher.

Zenith used European-made 6HA5 in their GVG (Gold Video Guard) VHF tuners and my experience doing "difficult area" antenna work (with such tuners confirming reception) confirmed both were about equal in both sensitivity and durability. RCA's, Sylvania, Philco and Zenith in particular were among the best for such areas. If customer had a GE, Magnavox or Japanese set other than Sony, we usually had to up the antenna game.

I suspect TVs and FM sets used in strong signal areas were hard on UHF and VHF tuner RF tubes, despite AGC action that attempted to pull the grid negative toward full cutoff, the cathode was still hemorrhaging electrons. I have 500(!) NOS 6AF4 tubes from the huge tube lot I bought 8 years ago when Harrisburg Radio Lab closed. The 'burg had three UHF transmitters since 1952, and shops in the area were obviously replacing these tubes for a reason.

[Firedome]

Interesting how antenna and station signal performance was reflected in the tube inventory!
I looked in my inventory and have 1 ea of 6CW4, 6DS4 and 6HA5 for the various stuff I have.

[electra225]

I have a collection of Consumer Reports magazines from the 1959 to 1963 era. It is interesting to read the comments CU made about consumer electronics products we now hold in high regard. They were not so enamored in many cases when they made their analysis back then.

[TC Chris]

I've probably said this before, but CU didn't much like the '92 Ranger. "Rides like a truck," they observed. Well, thought Chris, it IS a truck, so maybe there's a reason for that. Would anybody (apart from the posers who buy a truck to look cool) want a truck that handled like a Lincoln? You'd have to load up on sea sickness remedy.... So I always consider CU's comments in context.

Chris Campbell

[Firedome]

Hey Lincoln made a pickup truck, wonder if it rode like a truck? lol
I always thought Lincoln and Caddy should stick to cars and leave the P/Us and SUV to Chevy, Ford and Toyota.

[Motorola minion]

So far I have looked up a few schematics on these consoles listed. Most are tubed and, in an emerging solid state market, these players were bargains at the time.

The Fisher P-290 is all tube with PP 6HU8 output tubes.

The V-M 954 uses SE 6BQ5 outputs, like earlier models.

The Motorola SK191 uses Germanium transistors for audio driver and outputs only, rest is tube and much of it on a Printed Circuit board.