Vauxhall Type VR Car Radio

[G6Tanuki]

Originally Posted by Boulevardier

Ah, Bowden cables. I hadn't thought of that. This must have made such a radio a very expensive accessory to fit to a car, and presumably factory fitted.

Expensive, yes. And remember that 'back then' you also had to pay extra for a car-radio licence!

Even in the mid/late-1960s only distinctly-upmarket cars came with a radio fitted as standard.

[Heatercathodeshort]

The radio was in two halves. The tuner up to the detector stage was in the 'head unit' usually mounted in the dash board. Another steel box connected via a multi core cable contained the audio amp, either single ended or push pull and the vibrator power supply. This unit was mounted on the bulk head under the bonnet. I will dig my HMV 100 [1948] out. I know where it is but the strange noises in the loft above the garage frighten me...I will see what I can do. John.

[TonyDuell]

My late father bought a near top-of-the-range car in 1974, it came with a radio which was somewhat unusual at the time. Just a MW/LW transistorised set with pushbutton tuning. Lower models in the same range generally did not come with radios.

I have a couple of 2-unit valve car radios :

One is a Radiomobile. The tuner unit is about the size of a 1970's 'spindle mount' transistor radio. It contains 4 B7G based valves (RF amplifier pentode, frequency changer heptode, IF amplifier pentode, detector, AVC and audio amplifer double diode triode). Push button permeability tuner. The amplifier unit is rather larger and contains the vibrator power supply (metal rectifier) and 3 valves (ECC83, 2 off EL84) as the push-pull audio amplifier

The other is a Blaupunkt. The tuner unit is rather taller than a spindle-mount car radio, but still very compact. The amplifier is quite small, vibrator power supply and a single EL84. The reason the tuner is large? It contains 6 B9A based valves. Mind you it does cover MW, LW and VHF FM, and it does have (electromechanical) seek tuning.

I am told one reason for having at least the power supply as a separate box is that it could be mounted under the bonnet (rather than behind the dashboard) so that the people in the car weren't annoyed by the buzz of the vibrator.

[emeritus]

The only person I knew who bought a licence for their car radio was one of my fellow students. As he was a Post Office apprentice, he felt obliged to. He had an old Standard Vanguard that had a two-part valve radio. It wasn't wired via the ignition switch, and when he inadvertently forgot to turn it off one night, the battery was flat next morning. That was in the late 1960's.

Did they scrap the radio licence when we went decimal? AFAIR, that was when they scrapped a number of relatively small fees, such as dog licences (7/6d) and the 2d stamp duty on receipts and cheques.

[Heatercathodeshort]

Pictures of the first Radiomobile car radio model 100 c. 1948 manufactured by HMV/EMI.
It employs loctal valves of a similar size to the GT/G octals. I have the loudspeaker somewhere in it's baffle. This could be mounted in any convenient position inside the car. The rubber grommet can be seen where the interconnecting cable passed through the bulkhead.
These radios were only fitted in large saloon cars. This one was removed from an Austin 16 from the late 1940's.
It works incredibly well and only required a few caps to restore it to good working order. Regards, John.

[Heatercathodeshort]

Internals of the head unit. Six valves, single ended output stage and rectifier.
A small internal speaker is provided with extension into the rear.
The radio fitted in the early Velox and Wyvern models was somewhat smaller. B8A valves became available around 1950. John.

[Hartley118]

My first car was an elderly (1956) Rover 90 which came fitted with the excellent Radiomobile radio - something of a novelty back in the 1960s. I recall going to the Post Office and proudly buying my car radio licence. It made sense, not only as an honest citizen but also because it was the one item of radio gear that was clearly publicly visible with an associated car registration. And yes, AFAIK, the car radio licence requirement died in 1971 along with the general requirement for a separate radio licence.

ISTR that the radio was wired independently of the ignition, so there was a risk of leaving it on and flattening the battery, but the gentle hum of the vibrator was a useful reminder - and there was always the starting handle to get me out of trouble!


I’ve always been impressed that those early car radio designs paid attention to proper optimum matching of the short aerial and its associated feeder cable. Whilst the average domestic set still assumed a 50-foot aerial suspended down the garden, Radiomobile and presumably their competitors achieved remarkably good signal to noise from a 2-foot roof mounted whip. I recall that as teenagers we recognised that the best reception of Radio Luxembourg was to be had in a friend’s Aunt’s car with its Radiomobile radio.

Martin

[Boulevardier]

Originally Posted by Heatercathodeshort

Internals of the head unit. Six valves, single ended output stage and rectifier.
A small internal speaker is provided with extension into the rear.
The radio fitted in the early Velox and Wyvern models was somewhat smaller. B8A valves became available around 1950. John.

Thanks for those pictures John. I had forgotten the loctal and GT versions of octal valves - quite a lot smaller than standard octal. I'm a bit puzzled as to how they managed for IF/RF transformers. Did they by then operate with the lower (250-ish Kc/s) IF that would allow smaller and less obvious transformers? I can only see two components that could be smallish inductors/transformers. But perhaps they were all-TRF.

Excuse my ignorance - not my "special subject" (not sure what is!).

Mike

[Heatercathodeshort]

No Mike, standard I.F. frequencies, just good design. A TRF car radio would be a disaster being too insensitive and just not selective enough.
Most car radio's had an RF stage that helped a lot. I did have a pre war Philco with large UX based valves. That was all in a square box complete with the speaker that bolted anywhere it would fit! I gave it away years ago.
The Vauxhall ones were very neat and tidy leaving just the pre set tuning wheels protruding through the dash [in the Velox and Wyvern] together with the volume on/off and manual tuning controls. It was a long time ago. John.

[alanmoore]

Hello John , love the pictures of the old car radios,. One thing that I was wondering about is that were the AGC circuits more complex than a domestic AM superhet ,as the signal level is changing constantly as the car is being driven around ?
Regard Alan.

[Heatercathodeshort]

Looking at a few contemporary circuits they follow the standard practice of the home radio of the day. There is a lot of power supply filtering due to vibrator hash but other than that, nothing special.
Back in the day a five valve + rectifier with an RF stage was a formidable piece of home broadcast receiver and the car versions certainly worked well.
If I can find another I will post. J.

[Heatercathodeshort]

Found it! Minus a knob unfortunately. This is the actual radio for an early Vauxhall Velox. It is manufactured by DELCO REMY HYATT a division of General Motors.

Just 4 valves in this one. No RF stage and I presume a synchronous vibrator/rectifier. Loctal valves again. It fitted behind the dash with the rotary presets etc protruding through the grille.

I must say it has a PLESSEY look about it but that is only a guess. My mate's one worked very well. I think it was a 1952 model. John.

[Boulevardier]

John, Do you know what the valves are?

[Techman]

I've got several old valve car radios. They're all buried somewhere in the loft and I'm not going up there right now to find them. I may have some old photos of all of them on file somewhere and I've found the most recent ones of one of them which I'll post now just for interest:-

[Heatercathodeshort]

I'll open it up and check the valve range for you.[sorry I don't know your name] Interesting thread. John.