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MG TD TF 1500 - Radio Wiring

I am restoring the TF. I have instrument panel out.
I have an original radio I am going to put in in - I have converted to Neg ground. Question - I am wondering if I should ahead of time put some kind of wire off the ignition like a spade connector that I can just plug the radio into without trying to later get another wire to the ignition? If so - can anyone tell me the posts on the ign switch I should put it if I want it to be hot all the time, or if I want power only when the ignition is on? Also want to run a ground to the radio - any suggestions where to ground on the car?
Keith in NJ
K E MURPHY

Always hot all the time is the brown circuit. You can go to the brown wire at the ammeter (probably stick the wire under a grub screw... I have a TD not a TF) which comes directly from the battery via the mechanical starter switch. Use bullet connectors instead of spade connectors for a more authentic look. I would put an in-line fuse on it for the radio. A good ground point is anywhere on the tub where a black wire is... for example where the panel lights ground out. or scrape a bit of paint under a nut. You can check for the ground by placing a test lamp between the brown wire at the ammeter and the place you want to put the ground (battery has to be hooked up for this). If it lights, it's a ground.

warmly,
dave
Dave Braun

Oh, and power with the ignition on is the white circuit. So at the ignition swtich, put it there for a switched circuit. And the power all the time on the ignition switch is the brown with blue stripe, that comes from the regulator, but should always be hot. Green is switched and fused. One goes to the petrol warning light and the screen wiper and the turn signal switch. Those will all come on with the ignition switch and go through the fuse on the firewall first.

warmly,
dave
Dave Braun

Thanks so much, exactly what I needed.
The radio already has one of those inline fuses in a black holder that unscrews. I probably should fuse
the Arnont heater too? Wonder how many amps.
I am in the middle of restoration - saw some of the old messages and maybe can do a fuse for headlights, side and tail - could I put it under the dash close to switches where it wouldn't show?

Keith
K E MURPHY

Keith, you're welcome. On my website under 'Technical Index' is an article I wrote about fusing the TD's headlamp circuit. You might want to go there and check it out. Remember, fusing protects wires, not equipment. I figured that it makes sense to fuse anything that draws a decent current. I wouldn't put the fan on the heater in that class. I think I would simply put it on the green circuit (switched and fused) and take advantage of the fuse in the fuse block.

You can determine the draw simply enough by hooking the fan to your battery with a digital multimeter in series to measure the current flow (amps). Try it on the 10 or 20 amp setting first. Your alternator probably puts out between 19 and 22 amps.

warmly,
dave
Dave Braun

I have a 1954 mgtf & wish to install a new Sony FM Car Radio but the radio is negative earth yet the car is positive earthed.Can anyone advise how to handle this matter?
D JOHNSTON

D Johnston.. The safest way would be to convert the care to Negative ground. It is extremely simple to do and that way you dont fry the radio or cell phone charge etc.
Sandy
SANDY SANDERS

I would go one step further than Sandy does and state DO NOT INSTALL A NEGATIVE GROUND RADIO IN A POSITIVE GROUND VEHICLE unless you really like the smell of burning insulation in the morning. No matter how well you think that you have the radio isolated, all it takes is some small slip to incinerate your wiring. If I remember correctly, Gordon L can back that up. Additionally, without the radio grounded directly to the body of the vehicle (which you cannot do it the polarities don't match), you will have very poor reception. Cheers - Dave
David DuBois

K E Murphy,
You say you have an "original" radio. (Do you mean a period add on??)

Is it Positive or Negative Ground?????

If it is "original", it is Positive Ground and can't be used in a car converted to Negative ground.
Don Harmer

The most common mistake I have seen over the years of helping others with "trans-gender" radio installs:
The Antenna! I have seen all sorts of elabarate plans to isolate the 12 volts go up in smoke because most antennas are grounded to the body.
IMHO: If you are going to put a radio in the car, make sure it matches the electricial system. Like Don said...if it is a period radio it should be poss ground already so no problem. If your going to install a CD player (or moderen radio) changing the car to neg ground is fairly straight forward and easy to do. (a lot easier than replacing a fried wiring harness!)
MY TF is neg ground and has quite a few fuse mod's done to it. Don't have a radio (I like listing to the exhaust note better) but no worries with the cell phone/gps and other accessories.
On a long trip ...one word : IPOD.
Crispy, Burnt T cars are a sad sight!
David Sheward

Converting to negative ground is as easy as turning the battery around and reconnecting it. That will get the car running. It will have a few faults as listed below.

1. The ammeter will read + when you turn the headlights ON. Swap the two wires connected to the back of the Ammeter.

2. The spark will not be as hot as it used to be. Swap the two wires at the coil.

3. If the car is equipped with a solid-state voltage regulator return it to the shop that built it for change over.

4. If the car is equipped with the original helmet style battery connectors change them to standard American types.

That's it, have fun!
Cheers,
Bob
Bob Jeffers

Also, if you have a electronic fuel pump for + ground, need to be changed.
Bill
Bill Brown

One more, Bob --- how about repolarizing the generator? Bud
Bud Krueger (TD10855)

I use a Creative Zen MP3 player transmitting sound through battery driven speakers in a small padded box. It will store something like 100 CDs and has a reasonably good FM receiver. Wrapped in a synthetic fake Burberry silk scarf in the passengers glove box it is out of sight, while allowing me to hum along with Vera Lynn, Glenn Miller, Django Reinhardt or other period masters of song at low speeds. At high speeds I need no music.

Regards,


jan


Jan Kristoffersen

Bud--- You mean you want to charge the battery? Why in the world would you want to do that, in this day and age of green things.

Seriously, Bud nice catch, thanks.
Cheers,
Bob
Bob Jeffers

....yep...I insulated everything....bought a fancy electronic antenna that took power from the 'blue' wire (auto raising lead)...mounted the radio in a center armrest and put cork insulation over the handbrake....
Over a year, the radio slowly rubbed throough the cork and grounded out on the lever..... amazing how much smoke the inside of a TD (with the top up) will hold...... smelled good too.....!!!!
gblawson(gordon- TD27667)

OH YES!
Here's a little tent creeping music for ya!
Sing along if you know the words...I'm betting you do.

http://www.youtube.com/watch?v=o6jwvS0mHwo

Jan...I'm not going to get anything done today...there's a lot of Django on You-Tube!
David Sheward

Youtube is such a great website. Your tip gave me the opportunity to see some Django Reinhardt and Stephan Grapelli footage tonight.

regards,

Jan
Jan Kristoffersen

Jan ...Thank you...I never thought of looking there till I saw your post. Been a fan for a long time. Just amazing that Mr.R could play like he did with two "dead fingers"!
I got little done today ...but it's snowing outside so good day for some excelent tunes!
David Sheward

Hello David,

This is really straying off topic, but I ended up on Youtube yesterday evening ( it is 8 a.m. in Oslo now)
I found this lovely collage of pics and footage from the movie Casablanca coupled to Stephan Grapelli playing "As time goes by" on the violin. Magic!

http://www.youtube.com/watch?v=0FogmcygI3A&feature=related


MG-connection: Best played with engine turned off.

regards,

jan Emil
Jan Kristoffersen

A must Christmas present for your MG friends.

http://www.youtube.com/watch?v=b9XAC-BvUyo

Mike
Mike Hart (52 TD 16378)

Jan,
"Grapelli" ...what can you say ...the guy has got to be 1st chair where he is playing now! (Heaven)
Thanks ...that was nice.

Mike, LOL ...sounds just like the car on an old video game we have for a Magnavox Odesey!
Not for the TF ....but hmmmm... wonder what that would sound like if I strapped a sub-woffer to the "Ranch-King"?
Better not ...I allready get enough dirty looks when I mow wearing my "If you can read this, the Bi**h fell off" T shirt.
David Sheward

This thread was discussed between 12/04/2009 and 04/12/2010

MG TD TF 1500 index

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