Classic cars forum & vehicle restoration.

[CWhaley1]

Hello - I'm currently in the process of restoring a running Super Minx from 1965. The radio I salvaged from another Super Minx of the same year can be seen below but I have no idea how to wire it up. The aim was to test from a spare 12v car battery I have but I can't figure out the connections on the back, aside from the obvious aerial connector on the left. The last picture shows a connected dial I'm also unsure of.

Has anybody with electrical experience got a clue as to how I'd test this unit? The car currently has no audio equipment as standard and is positive +ve earth, so the aim would be to reverse polarity to negative earth and fit a speaker to the parcel shelf as it would have been. The aerial cable is already there tucked under the back seats.

Not sure of the age of the unit but I'd say it's got to be mid to late '60s based on some of the paper warning labels and general styling.

Thank you!

[norustplease]

The only real way, unless you have some electronics experience and test gear, is to do a jury rig and see if it produces any sounds. Presumably it says somewhere on the case whether it is positive or negative earth, (presumably positive earth if from another identical Minx) and you should be able connect it to a 12v battery accordingly, which if it lights up when switched on, should indicate whether it is live or not. If you connect it to a speaker, using the output connections, then that will give a further idea as to whether the amplifier is working, since you should be able to hear it switching on and off and obviously, connecting to the car aerial should produce some kind of reception. However, the radio may not be FM, and if not, will have relatively few stations to tune to, and may not actually be much use in its current state. If that is the case, it is probably best to pack it off to a specialist such as Tadpole, who will covert it to FM for you and give you a period looking radio with modern performance. They will also be able to change polarity to match your car's proposed negative earth status.

The connected dial maybe a fader control to allow a balance to be struck between front and rear speakers. This was a fairly common period modification with additional speakers to those in the front, fitted onto the rear parcel shelf
Don't let dangling speaker wires touch each other when the unit is switched on as damage can result.
_________________
1953 Citroen Traction
1964 Volvo PV544
1957 Austin A55 Mk 1
Boring Tucson SUV

[CWhaley1]

Thanks a lot for the reply - I will check but I believe it is positive earth. Although taken from a Minx that was negative earth when I got it, I believe it was not originally this polarity when made.

I did always wonder what the 'vent' on the dash was for - other Minx's I have seen have had a speaker on the parcel shelf but I presumed this was original. Unfortunately I'm not old enough to remember the little modifications like this or the door mirrors and reverse lights people used to adapt to their cars.

It doesn't have FM no, but I listen to stations on long and medium wave including a couple of stations playing older stuff which would go with the car. Eventually I'd probably like to hook up a more modern unit with FM, but I'd want this hidden away somewhere.

Of the wires on the back am I right in saying the black wire on the right is the positive cable and the middle wires (with block) are for speaker?

[CWhaley1]

A very faded paper label underneath the radio says 'warning - for use on vehicles with positive earth'. At least now I know the power in should come from the negative end of the battery, with the ground/earth being positive.

[kevin2306]

Ive had mine converted to allow me to hook an mp3 player to it via a small cable.
They are great looking sets and really add something to the interior of the car, My wife however thought I had lost it when I bough an additional 2 sets so I could change one control knob and the front fascia panel from them onto my set!

Kev

[CWhaley1]

Not mad at all, they just don't understand what we strive for in our cars! It can get a bit out of hand though when one individual part doesn't quite look right and you have to correct it...

I have a Motorla 717T I have just found out - I thought it was the 818T as they look almost identical at first.

[norustplease]

[CWhaley1]

Thanks for the info, gives me a little more knowledge to work with to get it tested. I've toyed up with the idea of wiring it up but just didn't want to risk it until I had a second opinion.

It was taken from a negative earth car yes, but was not actually wired up... There was another, more modern unit wired up and this Motorola unit was just left in the car in place, but unplugged.

In fairness I have no idea of whether or not it was converted for negative earth or left as positive! I think I'll take it apart and have a look to see if I can see the earthing connection.