[Engine-Ear]

Hi folks,

I am writing a series of articles to help folks figure out what components of a car's audio system works and how to test it without wasting time or money doing so.

Here is part 1 of the series...

https://redirad.com/blogs/news/colle...eration-part-1

Please read it and share with friends. I will post subsequent parts of the series as replies to this post. If you find any typos, send me a Private Message.

thanks!

[ornjcr8]

Keep it coming Matt, I can use all the help you can provide on this subject.

[Old Goat 67]

Doing good Matt!

[Pepi]

Good read so far, I like it!!

[Engine-Ear]

Thanks for the encouragement, guys.

I should have part 2 uploaded late this week.

[dataway]

Yep ... just pulled apart my original 68 AM radio for a look-see. Don't have an 8-10 ohm speaker for testing as yet (and I noticed an original sticker on the radio that said not to even turn it on without the speaker attached), also I need an old school radio antenna hook up to use with it.

Only problems I found was the pre-set mechanism which was solved with some light sewing machine oil on the little "slip clutch" thingie. And the tiny copper wire from the plastic coil to the antenna socked was broken so I had to resolder that.

Would love to see some info on testing the systems.

[Engine-Ear]

Originally Posted by dataway

Yep ... just pulled apart my original 68 AM radio for a look-see. Don't have an 8-10 ohm speaker for testing as yet (and I noticed an original sticker on the radio that said not to even turn it on without the speaker attached)

Right. here you go: https://www.amazon.com/Philmore-Squa...=8+ohm+speaker

Originally Posted by dataway

also I need an old school radio antenna hook up to use with it.

Yepper. https://www.bestbuy.com/site/metra-a...=ref:212,loc:2

Originally Posted by dataway

Only problems I found was the pre-set mechanism which was solved with some light sewing machine oil on the little "slip clutch" thingie. And the tiny copper wire from the plastic coil to the antenna socked was broken so I had to resolder that.

Would love to see some info on testing the systems.

Good detective work! More coming soon... go get those parts I suggested. Also, you might want to get some clip leads: https://www.amazon.com/s/ref=nb_sb_s...=2DY2L2Z5CULJ1 ...here's a bunch, depending on your needs.

If you don't have a 12VDC power supply, you can use a spare car or cycle battery. Don't use a battery charger!

[dataway]

Found the antenna on Amazon also, so bought it along with the speaker.

I've got a variable 0-30 vdc 10 amp power supply, typical adjustable voltage and current lab type power supply (can set to constant voltage or constant current), figured I would use that.

Would be a ton of fun to hear sounds coming out of that thing for the first time since 40 years ago.
Unit seems pretty clean and corrosion free, no obviously burnt out components, light bulb even still worked (different circuit than the radio).

Any chance you have a 60's era Pontiac AM radio on hand where you could point out the proper connections at the rear plug? They are labeled ... but the power in and the speaker out location seems kind of ambiguous. Don't want to fry anything by hooking it up wrong. I assume single wire to speaker with a local ground?

Thanks for the links, I'll post back in a few days after they show up and I can test it.

[Engine-Ear]

Connection description...

Rock on!

[dataway]

Thank you. I'll have the speaker and antenna in tomorrow .... see if I can get some sounds out of this thing.

[dataway]

Success! Took a bit of fiddling with the volume pot to get some sound out of the speaker, but with continued use it got better and less crackling. Brought in three or four stations with the antenna just hanging from a shelf and the whole thing in my basement shop.

This is a standard AM radio with front and rear speaker. The volume pot is a dual type correct? The white plastic sleeve around the shaft controls tone? Worst case scenario I have to replace the volume/tone pot ... doable? Available? While I might be able to find the same rated pot ... doubt I could find the right shaft configuration unless a vintage radio place stocks them. It works tolerably well now .... seems to get better with use. And I just want the radio to work for restoration purposes, it will not be used as an actual entertainment device

My GTO original had a switch tucked underneath the upper dash (like where the electric antenna control would go) which I think was a fader to the rear speaker ... am I remembering right?

Since there is only one "speaker out" connection on the radio I assume the harness had a splitter and one ran to the front, and one ran through the fader to the rear, or the main speaker out ran to the fader and the fader had one out to the front and one out to the rear .... I can look it up I guess.

So, Engine-Ear, thanks for the help. Seems to work pretty good, power transistor got a little warm, but from the size of the sink I assume that's normal. Wonder if that's replaceable too.

BTW ... this radio is in pretty much exact original condition ... looks like it's five years old. Still has the little stickers and such on it if anyone is curious about the minutia of such things.

[Greg Reid]

Originally Posted by dataway

Seems to work pretty good, power transistor got a little warm, but from the size of the sink I assume that's normal. Wonder if that's replaceable too..

Some fresh heat-sink compound might help.

[dataway]

Yep, good idea.

[Engine-Ear]

Originally Posted by dataway

Success! Took a bit of fiddling with the volume pot to get some sound out of the speaker, but with continued use it got better and less crackling.

Excellent. The crackly volume is dust+nicotine buildup on the pot (potentiometer) wiper and/or resistive surface. They can usually be disassembled and cleaned ONCE without the fold-over metal tabs breaking from fatigue.

Originally Posted by dataway

Brought in three or four stations with the antenna just hanging from a shelf and the whole thing in my basement shop.

Nice. Avoid the temptation and do NOT fiddle with the radio's antenna adjustment until it's back in the car and the car is in a parking lot somewhere (proper adjustment conditions, IMO).

Originally Posted by dataway

This is a standard AM radio with front and rear speaker. The volume pot is a dual type correct?

You mean for front and rear speakers? Sort of. Need more info.

Originally Posted by dataway

The white plastic sleeve around the shaft controls tone?

Yes, on the left shaft.

Originally Posted by dataway

Worst case scenario I have to replace the volume/tone pot ... doable?

Yes.

Originally Posted by dataway

Available?

Never looked (don't have part numbers to search by) - If NOS ones are, please let me know.

Originally Posted by dataway

And I just want the radio to work for restoration purposes, it will not be used as an actual entertainment device

Hmm, that's too bad (it's part of the ERA, and IMO worth preserving (and celebrating!) just like the factory interior for all of its shortcomings (hot vinyl, glare from chrome controls, etc.)) and with a RediRad model AM/N on the scene you could port music from your (or your kid's) phone thru the now-updated system.

Originally Posted by dataway

My GTO original had a switch tucked underneath the upper dash (like where the electric antenna control would go) which I think was a fader to the rear speaker ... am I remembering right?

Yes, depending on the year and body series (A, B, F, G).

Originally Posted by dataway

Since there is only one "speaker out" connection on the radio I assume the harness had a splitter and one ran to the front, and one ran through the fader to the rear, or the main speaker out ran to the fader and the fader had one out to the front and one out to the rear.

Right.

Originally Posted by dataway

... I can look it up I guess.

LOL, well it is YOUR car...

Originally Posted by dataway

So, Engine-Ear, thanks for the help. Seems to work pretty good, power transistor got a little warm, but from the size of the sink I assume that's normal. Wonder if that's replaceable too.

You're most welcome! I am trying to give my knowledge away for the benefit of others. As for the DS-501 (power transistor), getting warm is the norm. It is replaceable but not commonly available anymore. Keep each speaker's impedance at 8 to 10 ohms and it'll probably outlast you.

Part 2 of the article series will be posted to "Matt's Madness" this weekend.

Originally Posted by dataway

BTW ... this radio is in pretty much exact original condition ... looks like it's five years old. Still has the little stickers and such on it if anyone is curious about the minutia of such things.

Please post the model and serial number that's on the paper label...and maybe a pic or two?

[dataway]

Attached are pics of the serial number/patent label and two pics of factory inspection marks ( I think ).

Any chance a pot wiper can be cleaned with electrical contact cleaner without opening it up?

[Engine-Ear]

Originally Posted by dataway

Any chance a pot wiper can be cleaned with electrical contact cleaner without opening it up?

In my opinion: NOPE. Heck, it's difficult to get contact cleaner into the vol/tone control (where it NEEDS to be) when it's removed from the radio and you have it in your hand!

PLUS, not all contact cleaners are created equally, and some will damage the resistive material (chemical interaction).

When I disassemble one of these, I use 99% Iso-Propyl Alcohol and industrial swabs (Q-tips on a wooden stick that don't get frizzy) and wipe them until the swabs are clean. I then burnish the sprung brass contacts and give them a SLIGHT bend for added contact force when they go back together.

Pics show what's inside...

[Engine-Ear]

Originally Posted by dataway

Attached are pics of the serial number/patent label and two pics of factory inspection marks ( I think ).

...basically the same unit I just finished for my dad's '68 Catalina (different model number and cast dash-interface plate) but electrically the same. Here is his...

[erikgto]

Originally Posted by Engine-Ear

Hi folks,

I am writing a series of articles to help folks figure out what components of a car's audio system works and how to test it without wasting time or money doing so.

Here is part 1 of the series...

https://redirad.com/blogs/news/colle...eration-part-1

Please read it and share with friends. I will post subsequent parts of the series as replies to this post. If you find any typos, send me a Private Message.

thanks!

Just tried the original AM radio in my 67 GTO.... the radio turns on, but all I hear is crackling noise from the speaker. Doesn't seem to receive any AM channel...


Don't know if this is a good foundation for a redirad or something.

Otherwise I'll disconnect it and hide a modern radio somewhere with modern CustomAutoSound speakers under the front seats.

Verstuurd vanaf mijn SM-T585 met Tapatalk

[Engine-Ear]

Originally Posted by erikgto

Just tried the original AM radio in my 67 GTO.... the radio turns on, but all I hear is crackling noise from the speaker. Doesn't seem to receive any AM channel...

...I think that may be because all analog AM transmitters have been shut down in western Europe - this introduces is the very elegance of RediRad for car collectors in your part of the world!

If you're hearing crackling, the speaker probably should be renewed, and radio may need an electrical cleaning and adjustment. ...Not surprising for something that's > 40 years old (and not expensive, either).

If your car is STOCK (not a pro-touring, etc. car), for the first time, you can port music from your phone or MP3 thru that radio, without the cutting, drilling or the added cost for something aftermarket.

It is also my understanding that folks there pay EXTRA auto insurance if the radio in an "oldtimer" is aftermarket. If so, ANOTHER reason to consider RediRad.

Originally Posted by erikgto

Don't know if this is a good foundation for a RediRad or something.

It completely depends on what YOU seek: At one end of the spectrum, there's a big thumping stereo and the 'invasion' of the car's body and upholstery to mount/hide everything, or on the other hand, factory original appearance, equipment, and yes, something is not going to win any stereo contests.

Originally Posted by erikgto

Otherwise I'll disconnect it and hide a modern radio somewhere with modern CustomAutoSound speakers under the front seats.

As I said above, you have to do what's right for your goals. (By the way, speakers that are hidden under seats will absolutely KILL the frequency response (the whole point of something aftermarket) of an aftermarket system.)

Send me a private message if you want more information. You can also check out RediRad .com for info, or YouTube for some videos.

Good luck with your decision...

[erikgto]

Never though about the AM signal being gone since I can listen AM radio in my company car if I want.

So I checked the situation again today.
I think the radio might be ok, I only hear the crackling when I'm fiddling with the volume or frequency knobs.

Btw insurance here doesn't really care or make any difference if a car is modified or not.


This might be a good redirad starting point.


Erik