Posted on Tuesday, December 04, 2007 - 13:48 GMTThe meters didn't even move a bump?Do try an input to it, the recording heads might still work, but without outputs, it will sound like a tree falling in the forest with no-one around.A signal tracer is useful, but does not replace a good meter.If you are so inclined, get to reading the power supply and it's associated protection bits, there are not many.The Ampex units I have fixed are different from the Akai, but that R2R is a reasonable unit, if you can find the tapes for it. Posted on Tuesday, December 04, 2007 - 14:01 GMTNuck, both meters did not move even the slightest.
Tape Deck Web Radio communicate different sort of Funk, Groove, Soul, R&B & Disco and so on Tape Deck Web Radio gushing music and projects both in on the web. Tape Deck Web Radio is 24 hour 7 day live Online radio. Crackle sounds with GR 5 and Asio4All. Discussion in 'Technical Issues - KOMPLETE. Actually, I don't need to be playing in order for the noises to appear. I can just load an mp3 into the tape deck and let it roll for a few minutes. The noise will come up. Now I get the Rice Kripees (snap, crackle, and pop) as soon as my VSTs start.
The original owner gave me some original recordings and some home made recordings. He showed me how to use it, so it can't be operator error. I am assuming the meters respond to a signal going to the recording head and a signal coming from the playback head. If the meters move at recording, do I assume that I have a bad playback head? As far as reading the power supply and protection bits, I'm not sure where to check this. The power indicator lamp comes on and all moving parts work, so the power is making its way in.
I am assuming that there is some DC conversion somewhere, and not sure where this might be. Posted on Thursday, August 04, 2016 - 01:28 GMTJan, I see your point. I just got lucky, I guess.Another akai that i have, a 1720, plays just fine but when I try to rec, i get nothing on the right channel and a loud cyclic thump on the left.It was working fine about a month ago, then it started to peak the rec level (it was recording normally and suddently the vu level peaked to the end of the red area like it was maxed out) and about a week later, it stopped getting any signal.Do you have any insights on what i should look into?Thanks in advance,MG. Posted on Thursday, August 04, 2016 - 11:45 GMTI have the schematic for the 1721W/L but I read somewhere that they are the same between the 172. series, so it should work fine for the 1720.
(aside the front panel, they do look like twin machines)I can sort of read a schematic. I mean, I can understand and identify the individual components but I'm not too keen on knowing their function as a circuit.The image is to big to send it here and when I try to shrink it dowm, it looses legilibity. Can I send it by email?Best regards,MG. Posted on Thursday, August 04, 2016 - 19:32 GMT.There's no point in sending the schematic. I don't have time to go through a troubleshooting process on an old Akai and a forum is not set up for that sort of work.I would first send you to my previous comment in this thread; I would ask you to read this;have a schematic, you need to learn how to read it and follow the flow of a circuit.Then you'll need a DVOM for measuring signal and Voltage flow, a signal generator and an oscilloscope.
Plus some amplification and speakers to listen through. You'll need more gear but we'll get to that in a minute.You'll need to identify the various circuits inside the player so you know what you are inspecting. Input, output, power supply, eq, etc.You will most definitely need to know where to place the probes of your DVOM so you don't blow up the circuit or possibly electrocute yourself.Don't take that last bit lightly, electrocution is always possible when you are sticking your hands inside a component with 120 VAC powering through it.Then you will need a space where the deck can be disassembled and laid out for how ever long it takes to locate the problem components and have them shipped to you for installation. If you are unsure of how to troubleshoot a circuit, then you'll probably blow up a few parts before you get it right.It's a fair assumption the unit was defective before it was put on sale.
Old stuff is almost never in good shape.Even if it was in perfect operational shape at the time, thirty and forty year old components have parts which have drifted or simply gone bad. Posted on Thursday, August 04, 2016 - 23:18 GMT.Start with this; make a list of ALL OF the replacement parts a 35 year old reel to reel will most likely need.Figure all rubber parts.Power supply caps.Look for ic's and transistors which may no longer be available.Look at the heads and determine if they have enough wear to indicate they might need replacement.
If there is a groove worn into the head, it definitely needs to be replaced.Make sure ALL of those parts are easily available before you even begin to troubleshoot the deck.There are several parts which could have been specific to this series of decks. A few parts simply will no longer be in production.If you have even one critical part to the restoration which is unavailable or outrageously expensive, then there's no point in going further. Posted on Friday, January 04, 2019 - 06:27 GMTReel-To-Reel is a very complex machine.Even IF the electronics is perfect you still must deal with a fairly complex MACHINE.Sometimes special tools are needed. Spring tension gauges. Special lubricants (spec'd by manufacturer) andthan the selection of mechanical parts which are frequently made of UnObTanium. You can probably get or fabricate from existingparts, stuff like pressure pads and certain non-critical springs, but try for a capstan IF yours is rusty, bent or frozen in its bearings.My Tandberg had ONE motor.
But while it was playing, the take-up reel was wanting to go fast. This is normal for all tape machines and providestape tension.
BUT, the FEED Reel had 'backspin' applied to it so the tape path over the heads had NO pressure pads, just the pinch roller at the capstan.That was a very complex machine with dozens of linkages, lubrication points, o-rings used as 'belts' and even a CrossField head tossed in for goodmeasure.As for CPfirezine, above? You've got a clutch from the motor to the feed reel. This allows the motor to spin freely while power is supplied to reel.Does it rewind properly? You might need to adjust clutch tension to provide 'friction' so it unspools less freely.This clutch is shot or needs repair.
It has insufficient tension. Is the Dokorder a3-motor design? If so, it's even worse. If a single motor, it sounds like a mechanical adjustment to the feed reel. Posted on Friday, January 04, 2019 - 15:06 GMT.IMO a reference to a Tandberg tape machine to a question about a Dokoder is like comparing a Ferrari to a Chevette.
Similarly, how one was built has nothing to do with how the other was built. It also has nothing to do with the relative value of the Dokoder/Chevette.A point to be taken from the discussion though is how much value you would ascribe to a vintage piece of electronics.
If there are sentimental reasons for owing the Dokoder, there is no value we can give to repairing it. You spend what you want to spend if you wish to have a sentimental keepsake. Otherwise, I'd have to say putting much money into the Dokoder is similar to putting money into a Chevette with 180k miles on it.Parts wear out and, particularly if the machine has been in storage, parts die. I'm unaware of any club that is dedicated to saving old Dokoders so you're going to have to find vintage parts for certain repairs or jerryrig parts intended for other uses to your repair. You've given no indication you can complete the repair if you can't diagnose the problem. Therefore, I assume most repairs will require a technician willing to take on a Dokoder.Before we diagnose something over a forum from a distance, I'd suggest you find a tech in your area willing to do the work.
Otherwise, what we guess at will mean nothing. We aren't spiritualists who can devine problems from a distance. You need hands on assessment and an estimate of costs.It would be the very unusual tech who has specs for the Dokoder and an even more unusual tech who would care to take on the repair IMO. Most techs, if they are any good at all, have been saddled with a vintage repair where other parts are simply waiting to fail. They've learned their lessons from such repairs and don't tend to repeat their mistakes.My guess, and it's only a guess is the belts have dried out and stretched out. But, even if that's correct, that's only the first issue with a 50 year old reel to reel.
I would want to look at the entire machine before I even invested a dollar in the Dokoder. Even more parts might need replacement and adjustment.My advice would be to not spend anything on the Dokoder. Find a vintage Tandberg with Dolby noise reduction if you want to use a reel to reel. Don't pump cash into a dry hole. Have something worth having when you're finished.If you prefer to ignore that advice, find a tech who will work on this machine before you go any further. Posted on Friday, January 04, 2019 - 23:12 GMT1) I want to play old tapes that I recorded in order to digitize them. Some are true four track recordings, so playing them on a 1/2 or 1/4 track machine won't help.2) If I know what the problem is, I can do the work myself.
My intention was to ask if anyone had an idea or had the same experience. I have the original manual and the schematic is in there, though I doubt that it's an electrical problem3) I know it would be foolish to drop a lot of money into this machine.
That's not going to happen.Thanks for your replies. If anyone can give me good advise on the machine, I'd appreciate it. Posted on Saturday, January 05, 2019 - 00:00 GMT.IMO we have given you good advice.
Even if it comes down to replacing a belt, this is still a vintage component - possibly pulled from decade's long storage - with other parts that are likely to break in the near future.Generally, if you can't do the diagnosis, you can't really do the repair yourself either. You can guess, but that gets expensive, particularly on a deck that isn't known for parts availability.That's why techs existed with a shop full of tools and repair manuals and they went to school to learn how to do repairs.Can you read a schematic and follow the signal path and the power supply path from input to output? If you can't, having a schematic doesn't help you at all. You need a tech who is willing to work on the machine and bring it up to OEM specs.Vintage tape decks typically require a complete renovation to remove the old grease - which has probably thickened and may be the source of your problem - and replace it with fresh lubricant.How are the heads? A worn playback head does you no good. Most Dokoders had permalloy heads which were notorious for wear. If it is a model with ferrite heads, the performance is not as good.
Most reel to reels require adjustments to the tracking of the tape oath on a regular schedule. Do you have the information and tools and equipment to do that?You might look into services that digitize tapes. In the long run, it will probably be less expensive and better quality. Even if you have a 'reel to reel' deck, if the EQ set in the recording is not the same EQ as the playback machine, the tapes might not sound very good.If the deck doesn't have Dolby NR, it is now considered one of the lowest sources as far as sound quality is concerned. About the same as AM radio.So, what type of system are you going to play 'true four track tapes' through if you get this machine up and running? Posted on Saturday, January 05, 2019 - 16:47 GMTOK, again - half way through playback of the existing reels in my collection, the problem goes away.
This tells me it's not a worn head. Some of what I'm able to playback sounds pretty good. I'm aware of the issues old tapes have with regards to sound quality. This is true with analog tape no matter the format. I'll decide what I'm capable of fixing, thanks. I can read a schematic.
I'm an electrician. As you probably know, most music is recorded on multi-track systems. It doesn't mean you need four channels for playback. I do all my current recordings an multi-track digital software and mix them to stereo. I have figured out that because the deck will play tapes fine from about the mid-point of the reels, that I can feed all four channels into a digital 16 track digital deck I have, record each separately until the tape runs out, flip the tape, fast forward, and repeat the process.
Then I edit them back together, digitally reversing the audio tracks that played backwards and making sure the left/right aspect is correct if they're stereo or otherwise. A time consuming process. Then again, all analog to digital is a one to one transfer. My only time saver is that I can play back tapes recorded 3 3/4ips at 7 1/2', digitally stretch them 200%, which brings them back to proper time and pitch.
I wouldn't use this to record ANYTHING at this point, strictly playback of about 100 tapes I have stored from years ago. Posted on Sunday, January 06, 2019 - 00:04 GMT.Then I'd say you have this mostly figured out. You've asked for our guesses at the problem and we've given guesses. I never suggested heads were contributing to your specific problem. I mentioned the condition of the heads because most vintage decks would receive a suggestion to have the heads replaced in a refurbishment procedure.
If the heads are worn on a vintage deck, the problems of using the deck for anything other than a wall ornament begin to mount rapidly. If you're satisfied tapes can play back with adequate fidelity, you are the final judge of whatever quality you find acceptable.I'm sure you know the possible problems which might exist in your 100 tapes if they've been in storage for years.There are no others who will give you other guesses who contribute to this forum at this time. As I suspect you know, troubleshooting is seldom accurate when done at a distance as a good bit of trial and error is needed to assess mechanical parts. So, even if someone else showed up, they would very likely still be guessing.
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Actually, this was never a forum geared to repairs so the chances of someone else guessing, right or wrong, are rather slim.I would try new belts and possibly a pinch roller as rubber parts dry out rapidly if the deck has not been in use constantly. New lubricants wouldn't be a bad idea IMO. Leo suggests other repairs.That's the best we can do from a distance. I would still suggest you find a technician willing to do a refurbish on this deck.
If not that, look into either renting a four track machine for the time needed to transfer tapes or hand the job over the a service. Either of the latter two will likely save you a lot of headaches along with time and effort wasted. On the other hand, if you presently have more time than money.That's all we've got.As I've said, my experience tells me that if you can't manage a diagnosis, you probably can't finish the repair.
There are limits to my experiences. I've never sold Dokoder. Tandberg and Tascam, yes. And, to the best of my recollections, I've never even seen a Dokoder in any shop I've worked in so I've certainly never seen inside a four track Dokoder.
Tconway answered4 years agoJust had this problem. Radio comes on, no sound (or it would make a loudstatic sound if you hit the radio or ramdomly on it's own), everything else is fine,display, CD works etc. So I bought an identical used replacement radio onebay, still not working and the same problem.Then I found a post that suggested looking in the trunk and found that one ofthe plastic terminals for the wires on the rear speaker had broken off. Wiggledit, and the radio came on.Problem? Stuffing too much junk in the trunk caused the problem, it snappedthe plastic clip where the speaker wire is soldered in (connection was in factstill good), and then it shorted.Hope that helps. Maryemitch answered2 years agoThank You tconway!!!
Got in my car today and the radio poweredon, but no sound (other than a couple of static blips as I drovedown the road). Found this post after I got home, and it seems I,too, broke a plastic terminal while taking a large box out of mytrunk.
Re-positioned the plastic piece so that the wires no longertouched the speaker frame (?, the metal surrounding the speaker)and all speakers working like normal. Just saved me a lot ofanger, frustration, and money! Gabe answeredabout a year agoPROFILE: 2008 Toyota Sienna using standard Toyota JBL head unit. This Toyota has an entertainment fold-down DVD player that was installed at the dealer.SYMPTOM: Head unit appears to be work, however no sound is playing through any speakers. Also, entertainment fold-down DVD player is not working.PROBLEM: Toyota head unit is designed to stop playing sound upon any connection errors. In other words if a speaker, or auxiliary device is malfunctioning it will stop playing sound.
This includes anything after market or.extra installed by the dealer.SOLUTION: Disconnect the axillary device on rear of head unit, check speaker connectors (especially if your Toyota type has a trunk as the speaker clips are exposed and can be.hit by items in the trunk). In my specific situation, the Toyota installed DVD player in the back malfunctioned and put the head unit in this (NO SOUND) mode. Start with disconnecting as many interfaces on the back of the head unit as possible, and add from there. Do not disconnect the antenna though, this often serves as an additional Ground.