Old Delco 2700 "ETR"

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CrazyArk

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Just swapped out the original Delco for a retrosound, joys of phones jerking me around on a headphone jack... First and save for a special case, last time I monkey with this monster!

Question is, WHAT on Earth is this wired plug for on the back of my radio? I know the rest that I unplugged, but for the life of me I've no idea what the last wire that come out and dangles is for, is it part of the power for memory or something similar?

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Craig 85

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My '85 had an analog face to my OEM stereo and did not have those wires. Usually orange wires on our trucks is a battery constant hot. In your case, I would assume for the clock and preset memory.

It sure nice to have the OEM radio to get the knob depth set on the Retro Sound. I think that was the hardest part on the install.
 

Danderson

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The Delco digital radios with the clock have a separate 12 volt feed to operate the clock/PLL/memory chip, which is to enable the clock to run and keep the station presets loaded. It is usually on a separate connector on the rear, and gets a 12 volt supply from the battery even when the ignition switch is off. The radio will not function without both inputs, as the PLL will be dead. The orange wire is +12v battery supply wired into the fuse block and the brown wire is the "lights on" signal and is usually wired to the parking light circuit at the headlight switch.

Delco radios have a special place in my heart. My dad was an engineer at Delco Electronics in Kokomo Indiana from the late 60's through the mid 80's and worked on design teams for a lot of the radios during that period.
 
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CrazyArk

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The Delco digital radios with the clock have a separate 12 volt feed to operate the clock/PLL/memory chip, which is to enable the clock to run and keep the station presets loaded. It is usually on a separate connector on the rear, and gets a 12 volt supply from the battery even when the ignition switch is off. The radio will not function without both inputs, as the PLL will be dead. The orange wire is +12v battery supply wired into the fuse block and the brown wire is the "lights on" signal and is usually wired to the parking light circuit at the headlight switch.

Delco radios have a special place in my heart. My dad was an engineer at Delco Electronics in Kokomo Indiana from the late 60's through the mid 80's and worked on design teams for a lot of the radios during that period.

That is beyond awesome info to be given. A wholehearted thank you from me Danderson.

My only regret with my elderly Digital Delco is the fact the screen isn't lighting up correctly anymore. Amazingly it works, just can't see the stations. Cassette player kinda worked for running a cassette adaptor through though. But sadly I lack both the knowledge and the skill to fix it. As much as I want it fully functional to keep with the truck, even if it sits in a box with the stock speakers.
 

1987 GMC Jimmy

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F-Bodies had problems with screen illumination on the much rarer red face 2700 ETRs, IIRC. The orange ones not so much, but that’s not to say it can’t happen. If you haunt the 3rd Gen forums, you might find someone who repairs them, but there are people who work on them if you Google them.
 

Matt69olds

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The Delco digital radios with the clock have a separate 12 volt feed to operate the clock/PLL/memory chip, which is to enable the clock to run and keep the station presets loaded. It is usually on a separate connector on the rear, and gets a 12 volt supply from the battery even when the ignition switch is off. The radio will not function without both inputs, as the PLL will be dead. The orange wire is +12v battery supply wired into the fuse block and the brown wire is the "lights on" signal and is usually wired to the parking light circuit at the headlight switch.

Delco radios have a special place in my heart. My dad was an engineer at Delco Electronics in Kokomo Indiana from the late 60's through the mid 80's and worked on design teams for a lot of the radios during that period.


My dad worked at the Kokomo plant. Small world. It’s depressing to see what that plant has become. Dad hired in in 1970, he was one of the lady to “retire” under GM.
 

bucket

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I had one of those 2700 stereos, it came stock in my '88 Suburban. I really REALLY wish I would have kept it. I'd use it in my '78 Suburban.
 

Turbo4whl

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Here are a couple dusty old monaural radios for you viewing pleasure. But sitting in the basement next to them, in the second picture, some more old audio gear....

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You know what this is, and it was factory installed, but not in a square.
 

RoryH19

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Still have one in my 87.
One cool feature is you can check the time by pushing in the volume button when the truck is off.

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1987 GMC Jimmy

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I haven’t seen many 87s that have the 2700 ETR. That was the top stereo option, but most seem to have the 2700 analog versions, which is cool. They were all gone in the cars by then, and a lot of the ‘88 squares I’ve seen do have the 2700 ETR, and then ‘89-‘91 was the 2000 ETR. Moral of the story, I think 1987 was the last year for the analog units being installed en masse.
 

rt66paul

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Could those wires be for a power antenna?
 

Snoots

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Just swapped out the original Delco for a retrosound, joys of phones jerking me around on a headphone jack... First and save for a special case, last time I monkey with this monster!

Question is, WHAT on Earth is this wired plug for on the back of my radio? I know the rest that I unplugged, but for the life of me I've no idea what the last wire that come out and dangles is for, is it part of the power for memory or something similar?

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Got one of those in my square. Radio's dead but I play MP3's through a cassette adapter just great.
 

CrazyArk

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Got one of those in my square. Radio's dead but I play MP3's through a cassette adapter just great.

Mine worked that way just inconsistently, and with the fact my phone is one of those without a headphone port... It's "phone dies, or you have tunes" options. Add in the fact the face display had about 3/4 of its display not operating. Well, while I had the chance, time to upgrade the head unit, couple speakers, and add in the bluetooth i abuse heavily. Its going to take a repair tech to even figure out if my display is fixable or if I need to cannibalize another unit for the screen.
 

Snoots

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Delco radios are so much fun to work on
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