Guest The Goggi Posted July 27, 2009 Share Posted July 27, 2009 I have read many posts most from D-A-N-I-E-L (thanks for all the work). Is there a (1989) radio schematic out there somewhere? Should be able to disconnect the amp and run directly from the preamp some RCAs. This should allow for external amping and still maintain full use of the CRT for radio function. I will be acquiring a spare radio to "operate" on in a few days. Schematic would speed things up if available. I want to play around with the AUX input idea also. D-A-N-I-E-L 's work has inspired me to experiment (any news on a Chevy truck unit working w/ the EQ?) ... maybe a little upgrading throughout the radio would wake it up a bit. I will make careful notes to post later on. Link to comment Share on other sites More sharing options...
handmedownreatta Posted July 27, 2009 Share Posted July 27, 2009 daniel said that some cadallac radios are designed to work with external amps. Link to comment Share on other sites More sharing options...
Guest Richard D Posted July 28, 2009 Share Posted July 28, 2009 If you could find the voltage controlled amps you could tap off their outputs. I liked better when you could just tap directly off the volume control. Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted July 28, 2009 Share Posted July 28, 2009 Are yo looking for the internal radio drawings? If so I have them, but you will have to request a set from Delphi if you want a set. I do have a lot of ideas about what I want to do with the brain. I just do not have the expert know how to do what I would like. The down fall to tapping the preamp is that you will stil get bass rolloff from the factory EQ (or tone depending on the radio brain) The 1995 Caddy modle woks well for amplifing, but still has rolloff. The thing someone needs to figure out is how to reprogram the EQ to eliminate the roll off. I have a few other ideas, but they are even more far fetched than that one. Link to comment Share on other sites More sharing options...
ol' yeller Posted July 28, 2009 Share Posted July 28, 2009 Mine came with an amp and subwoofer installed. I am not an audiophile so I have no idea how they were installed. Daniel, if you'd like to look at it, I'd be happy to show it to you.Greg Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 28, 2009 Share Posted July 28, 2009 Are yo looking for the internal radio drawings? If so I have them, but you will have to request a set from Delphi if you want a set. I do have a lot of ideas about what I want to do with the brain. I just do not have the expert know how to do what I would like. The down fall to tapping the preamp is that you will stil get bass rolloff from the factory EQ (or tone depending on the radio brain) The 1995 Caddy modle woks well for amplifing, but still has rolloff. The thing someone needs to figure out is how to reprogram the EQ to eliminate the roll off.I have a few other ideas, but they are even more far fetched than that one.Yes ... internal radio drawings ... how do I get them?Seems to me that the actual amp/eq section is analog even though controlled digitally. There is probably an analog filter circuit that could be bypassed for the bass rolloff ... essentially cut the crossover out. I wouldn't think it would be a program thing, but I am not looking at the prints either ... pure speculation. Could probably upgrade some of the components in the radio to increase sound quality ... again speculation, but makes sense. Link to comment Share on other sites More sharing options...
padgett Posted July 28, 2009 Share Posted July 28, 2009 The 88/89 radio information is on the reatta.net web site under documentation (will have to register to get access). Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted July 29, 2009 Share Posted July 29, 2009 You must contact Delphi (delco) to get the internal schematics. They will mail them to you for free, if they are not on digits. I would give you mine, but I have no way to scan them into PDF as they are too big for my scanner. I will see if I can find one to use at work. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 29, 2009 Share Posted July 29, 2009 This has got to be one of the most helpful, selfless goups on the web. I have never seen a group so willing to help and spend time diagnosing problems for people they have never met. Kind gives me a little hope in the human race ... not to sound sappy but I am impressed. Link to comment Share on other sites More sharing options...
padgett Posted July 29, 2009 Share Posted July 29, 2009 Worst case I can scan almost anything but look at the 88 set on Reatta.net first (12 MB download) Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 29, 2009 Share Posted July 29, 2009 I am waiting for my password and login. I just registered. Can't wait. Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted July 29, 2009 Share Posted July 29, 2009 Padgett, That is them. The diffrent radios did not change too much internaly. So if some one can mod the radios with that I would love to know. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 29, 2009 Share Posted July 29, 2009 Not saying that I can, but I have "modded" other equipment and I do have some friends that are more electronically gifted than I could ever aspire to be. Its worth a try and prints would definitely help. I would share any info I learned here obviously.Seems that I was surfing and someone here got into programming some ECM or BCM mods. Does anyone have any contacts that have any experience with the radio programing? As I understand it, its is a simplified version of BASIC which I have a "basic" understanding of. If this is the case, I could wish and hope that a screen could be programed to control a cd player in a similar way to that of the cassette deck. My wish list is:1. control a CD from the CRT2. bypass the amp section and delete the bass rolloff circuit (if indeed it is a curcuit and not programing) to fully controll external amps.3. add an external input for the use of an iPod.I think the controll of the iPod through the CRT would be a little ambitious if not next to impossible, but who knows?I don't want to create false hope; I know you guys have been thinking the same thing for quite a bit longer and I may not get any further than you guys have. I would like to pool our resources and give it the "old college try". Link to comment Share on other sites More sharing options...
Ronnie Posted July 29, 2009 Share Posted July 29, 2009 I would like to pool our resources and give it the "old college try".Would that be considered doing it the "old school" way? Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 29, 2009 Share Posted July 29, 2009 Hey... watch who you are calling Old School. Creative low income engineering. And a passion for taking things apart that I can not put back together again ... ask my ex-wife.OK the old school way. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 29, 2009 Share Posted July 29, 2009 Padgett, it was your website that I saw some programing discussed.Is that a "want to" or a "done did it" thing about the reprograming? Any resources on programing anything in regards to the CRT display, language, function etc radio or otherwise? Link to comment Share on other sites More sharing options...
Guest Mc_Reatta Posted July 29, 2009 Share Posted July 29, 2009 The scans aren't terrific, but if you look at the schematic for the Audio Tune Board you will notice 4 capacitors (C320, 312, 332, 325) in each of the 4 paths between the preamp / mixer chip (U301 ICTV) outputs for the four channels (pins 19 - 21) and the inputs to the 2 audio amplifier chips (U303 DM 165) pins 3 and 13. If you intercept the 4 signals from U301 pins 19 - 21 before those capacitors, and route them to 4 RCA preamp output jacks along with a ground (pin 30 or 31) for each, you should get a preamp output with minimal roll off ,which you can then run to an external amplifier for the speakers. Should maintain all volumn, balance, equalizer functions that the radio has. Those 4 capacitors will definately act as a high pass filter and create bass roll off of some degree. Had to calculate without knowing more info on the circuit. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 30, 2009 Share Posted July 30, 2009 (edited) That is exactly what I thought ... you saved me a lot of time figuring. I have seen the "fix" for popping noises on another website "Reatta Owners Journal" Reatta Owners Journal - Radio Capacitor Replacement InstructionsIn the pic I'm assuming the brown ones are the caps (bass chokes) you are talking about since they are under the smaller heatsink for what I assume is the preamp (2-transistors/channel). This shows 6 green ones though ... Maybe the other 6 are to regulate the power to the preamp? The look too small for that though and the look like they are in the signal path ... Hmmm.Am I on the right track you think?Makes sense that it would cause noise if bad from power supply to the preamp. I don't have the login and passcode yet to download them so I'm flying blind so far. Edited July 30, 2009 by The Goggi clarifying (see edit history) Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted July 30, 2009 Share Posted July 30, 2009 My wish list is:1. control a CD from the CRT2. bypass the amp section and delete the bass rolloff circuit (if indeed it is a curcuit and not programing) to fully controll external amps.3. add an external input for the use of an iPod.I think the controll of the iPod through the CRT would be a little ambitious if not next to impossible, but who knows?1. I control a DVD with the CRT (via a intergrated steering wheel control unit modified to use with the CRT)3. Aux inputs are already on the radio brain/amp.Have not done the pre amp, but I use a caddy radio with only low level outputs on it. I am very interested to know if the tap in methode works. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 30, 2009 Share Posted July 30, 2009 Do you have info on that install? Pics? Mjaybe an old thread?How does the CRT control the DVD? Does it just access it or does it control it also? Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted July 31, 2009 Share Posted July 31, 2009 Just controls it. I will try to do a quick wright up this weekend. Basically the controls are standard GM for the time period. This ment that I could use a steering wheel control adapter to change the tape operation buttons to operate (through IR emitter) a half-din DVD player mounted in between the driver seat and councel. I guess you could mount it anywhere. I will write it up this weekend Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 31, 2009 Share Posted July 31, 2009 looking forward to it Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 31, 2009 Share Posted July 31, 2009 OK the weekend is coming and I still do not have access to the site to download schematics. Padgett, Daniel ... think anyone would able to scan what they have?I will have all weekend off to look at them ... I would like to get a parts list together and start to dig in. Link to comment Share on other sites More sharing options...
Rawja Posted July 31, 2009 Share Posted July 31, 2009 If Daniel mails me the schematics, I can run off copies. I'm an electrical contractor so I have a large-format copier that we use to copy blueprints. Just a thought. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 31, 2009 Share Posted July 31, 2009 Much appreciated for the offer, but no offense, I probably would not want to send out my only copy to anyone. But would accept the e-mail gladly if he did. Link to comment Share on other sites More sharing options...
padgett Posted July 31, 2009 Share Posted July 31, 2009 Non-Abs steering wheel controls were used in the 1986-1991 period on many Pontiac models.Controls are for both Radio and HVAC.That '90 Bonneville was the best 4-door I have ever had.I have the service manual insert for the SWC but it requires a collar on the steering column for the wiring. Link to comment Share on other sites More sharing options...
KDirk Posted July 31, 2009 Share Posted July 31, 2009 FWIW, some Olds Toronados also came equipped with steering wheel controls. These had a module that acted as a translator that captured the resistance coded switch outputs from the wheel controls and generated E&C bus control messages that would operate basic radio & HVAC functions. I've not seen the specs on the Pontiac setup, but would guess they were very nearly identical. Perhaps the regular yard scroungers here may want to start grabbing these modules for resale and reuse in Reattas, as it would make the addition of SWC's much easier for those who would like to do so. Of course, as Padgett pointed out there are other parts in the column. Airbag equipped cars have additional signal lines integrated into the clock spring coil for this purpose instead of the collar, but this is only useful for 1990 and up vehicles. KDirk Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 31, 2009 Share Posted July 31, 2009 UPDATE:Spoke with a guy at DELPHI and he is supposed to be sending me everything they have on hard copy.He said he has the Tech Service Manual that the repair centers use, intro to the interface system (I assume to mean the CRT) He said any of the part#s may be different but that a cross reference is available online or a service center would give that info. When I mentioned programming he said that he had all the pin-outs for the circuits and chips and that there was limited info on this. He then made some mention of how he hoped the CRT was working for me ... apparently there is no info on it.I inquired to the possibility of a Reatta prototype with the CD integrated with the use of the CRT and he said it may have something in it about programming but I would have to look.He was extremely helpful. If I am able, I will scan everything I receive for the forum.Supposed to be shipped Monday to my office. Can't wait to see what goodies are included.I am hopeful that maybe I will receive things that we "This Forum" have not seen before (not likely).I will update next week on this when it is in hand.<!-- google_ad_section_end --> Link to comment Share on other sites More sharing options...
Guest Richard D Posted July 31, 2009 Share Posted July 31, 2009 Goggi, I am interested in any schematics you can find for the Zenith CRT monitors and radios used in Reattas. Right now my cousin who is better at drawing schematics than me is trying to draw one from a monitor that was sent to me. I am more interested in the monitor section VS the touch screen logic circuits that mount to the sides. I would be happy to share the costs.Regards,Richard Link to comment Share on other sites More sharing options...
Guest Richard D Posted July 31, 2009 Share Posted July 31, 2009 Are those electrolytics for bass roll off or DC blocking? Maybe both?Richard Link to comment Share on other sites More sharing options...
Guest The Goggi Posted July 31, 2009 Share Posted July 31, 2009 The 6 small ones seem a bit small for bass rolloff ... I'm thinking that the larger brown ones are for that.I'm just guessing at this point though ... seems that the 4 would be in-line with the signal path for each of the 4 speaker outputs ... Link to comment Share on other sites More sharing options...
Guest The Goggi Posted August 1, 2009 Share Posted August 1, 2009 I couldn't wait for my info from Delphi and went ahead and opened up my radio box. Turns out that the 4 brown caps (the larger ones in the pic) are 100uF which puts the rolloff @ somewhere between 250hz and 500hz depending on the resistance @load somewhere between 4-8 ohms. These are likely the bass chokes everyone hates. The heatsink is all one piece and is actually the amplifiier and not the preamp. didn't look at it long enough for much else, but I will later.There doesn't seem to be but a very few components that could be upgraded and the expense would only be worth it on the items in the signal path.Unfortunately I will have to wait for my drawings before I can determine what components are in the signal path and what can be upgraded. Link to comment Share on other sites More sharing options...
D-a-n-i-e-l Posted August 2, 2009 Share Posted August 2, 2009 I will see what I can do with the drawing 4 U. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted August 2, 2009 Share Posted August 2, 2009 I appreciate it, but don't put too much effort into it yet as I will be getting them sometime next week ( I hope ) from Delphi. If not I'll hit you up for them.Appreciated. Link to comment Share on other sites More sharing options...
Guest Mc_Reatta Posted August 3, 2009 Share Posted August 3, 2009 Believe your looking at the wrong caps. The 4 100 mfd control the gain level that the amps are driven to. They are the ones that cause the cracks and pops in the speakers when they fail, but are not in the signal path. The ones that are, are the 6 (3 per chip) 1 mfd caps that are in the signal path between the preamp and the amp. 2 are used on the inputs pins 3 + 13 and one on pin 16 which I can't make it's use out per the quality of the scan. Possibly gounding input for both channels? Link to comment Share on other sites More sharing options...
Guest The Goggi Posted August 3, 2009 Share Posted August 3, 2009 I was just guesstimating ... you are probably right seeing as you have a guide. I was gussing b/c of the value ... 100mf seems to denote a higher cutoff than reasonable, but I had guessed that was why everyone was anoyed with it in the first place. See anything that looks like a high pass crossover on the prints?The math doesn't add up that the little ones would have anything to do with bass rolloff. They would filter out everything under about 40khz if in the signal path. I should really let it go until I have the prints, but my brain won't let me ... driving me nuts. Link to comment Share on other sites More sharing options...
Ronnie Posted August 3, 2009 Share Posted August 3, 2009 The 4 100 mfd control the gain level that the amps are driven to. They are the ones that cause the cracks and pops in the speakers when they fail, but are not in the signal path. Did you mean to say they are NOT the ones that cause the cracks and pops? The six green caps (1uf 50 volts) are what is normally replaced to stop the cracks and pops. Radio capacitor replacement Link to comment Share on other sites More sharing options...
Guest The Goggi Posted August 3, 2009 Share Posted August 3, 2009 As far as I understood it, the 6 green caps were the ones to replace for the pops and noises per the posts here. I assumed the 4 larger brown ones were bass chokes b/c of the placement and values being consistant with standard crossover values (my experience is in speaker and crossover building) ... I can not do anything but hypothesize at the moment. Has anybody done the 6 cap replacements that know why they were replacing them and what it accomplished in more specific tech terms? Link to comment Share on other sites More sharing options...
Guest Mc_Reatta Posted August 3, 2009 Share Posted August 3, 2009 Your using the wrong impedance # to figure the cutoff. You need to know the impedance of the amplifier chip input to know what the cutoff of the 1 mfd cap would be. I'm sure it was designed to roll off at the lowest frequecy the factory Delco speakers could handle before the distortion got too bad. My guess would be somewhere between 50 and 80 hz. Link to comment Share on other sites More sharing options...
Guest The Goggi Posted August 3, 2009 Share Posted August 3, 2009 I had a post to argue this point, but I am really talking out of my as% without knowing what I am talking about yet. It's all speculation for me at the moment. I will readress this later when I can validate what I am saying or confirm your point of view ... however it goes.You are likely right since you have some form of reference. Link to comment Share on other sites More sharing options...
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