Hi,
I recently own a nice old, Accuphase T 100 tuner. As I intend to refurbish, I was searching for the service manual to make a list of capacitors I need. Strange but true, all schematics I found indicate 4 PSU capacitors (2 x 3300/35 and 2 x 3300/25V) positioned on the left and right side of the transformer, but my tuner has inside only two capacitors of 3300/35V. There is someone to clarify that matter? Serial No. is 04Y663 and was bought from Germany.
There are also questions to ask if there are people who already done refurbishment to that tuner, just to change some info about and impressions.
Thanks in advance.
Victor
I recently own a nice old, Accuphase T 100 tuner. As I intend to refurbish, I was searching for the service manual to make a list of capacitors I need. Strange but true, all schematics I found indicate 4 PSU capacitors (2 x 3300/35 and 2 x 3300/25V) positioned on the left and right side of the transformer, but my tuner has inside only two capacitors of 3300/35V. There is someone to clarify that matter? Serial No. is 04Y663 and was bought from Germany.
There are also questions to ask if there are people who already done refurbishment to that tuner, just to change some info about and impressions.
Thanks in advance.
Victor
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Did you buy it new ?
If not somebody could have modified it ,all the circuit diagrams I have come across show 4 PSU capacitors -input to PS output from PS .
I would re-instate the capacitors to the original design ,nowhere can I find different mark numbers /versions .
Nobody has come forward so far to put a different view but if they do I hope they can supply a different mark number or deviation due to country of sale --apart from voltage corrections .
Companies sell electronic product that have standard specifications so that a worldwide product can be sold .
If they differentiate between countries then a different mark number/version is given and another circuit diagram is supplied differing from the standard one .
If not somebody could have modified it ,all the circuit diagrams I have come across show 4 PSU capacitors -input to PS output from PS .
I would re-instate the capacitors to the original design ,nowhere can I find different mark numbers /versions .
Nobody has come forward so far to put a different view but if they do I hope they can supply a different mark number or deviation due to country of sale --apart from voltage corrections .
Companies sell electronic product that have standard specifications so that a worldwide product can be sold .
If they differentiate between countries then a different mark number/version is given and another circuit diagram is supplied differing from the standard one .
Found a more extensive service manual. Maybe it explains the different versions
accuphase t100 tuner service manual Download page :: Schematics Unlimited
accuphase t100 tuner service manual Download page :: Schematics Unlimited
Funnily enough it still quotes 4 capacitors in---Internal View at the beginning although I cant argue with your photo.
Your right they have modified the circuit without changing the board serial number-719-0003-00 or model mark number its the same on my circuit diagram but shows the two missing capacitors yours doesn't.
Manufacturers have a disclaimer which states ="modification can take place without any notice " but the big question is WHICH is the later one ?
In all the designs I have come across later versions have modifications to improve sound quality and therefore -IMHO the 4 capacitor version is a later version as it adds two positions of extra smoothing.
But if anybody knows different ?
Good detective work Freebee !
Your right they have modified the circuit without changing the board serial number-719-0003-00 or model mark number its the same on my circuit diagram but shows the two missing capacitors yours doesn't.
Manufacturers have a disclaimer which states ="modification can take place without any notice " but the big question is WHICH is the later one ?
In all the designs I have come across later versions have modifications to improve sound quality and therefore -IMHO the 4 capacitor version is a later version as it adds two positions of extra smoothing.
But if anybody knows different ?
Good detective work Freebee !
Thanks, this one is the one with 2 x 3300/35V, I shall see if there are other different changes on the rest of the circuit diagram as I intend to complete a list of parts to be renewed.
I don't know if this is a later model or vice-versa, I can't understand why they have to renounce to capacitors at the out of the regulated supply.
Regards,
Victor
Good luck with the recap. You've got yourself a great piece. My advice is to compare the schematic to the actual values of the aluminium electrolytic capacitors in the tuner. Where space allows it go for higher voltage rating (new caps are significantly smaller except Elna Silmic)
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Could just be one from later in the production run. Not uncommon to find changes made on the fly during production that may not have made it into the service manual when it was printed. If you need help, check the Tuner Info Center discussion group on FMtuners@groups.io | Home
Generally removing parts is a cost cutting move...the bean counters getting involved. A few pennies may not sound like much, but with a production run of 1000 or more, it starts to add up. At least to some people's thinking anyway. Better quality parts tend to get more expensive with time also...and everyone in the company needs to make a buck. One of the reasons vintage audio gear gains appreciation...better build quality.
Finally, I have the schematic diagram with two 3300 uF instead of four. They are in the rectifier section before the regulator stage. I wonder why did they renounce at the two caps placed after the regulator?
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They probably determined that there was sufficient filtering without them and after a production run of 9 years, maybe time to cut some costs and leave them out.
Looks like it John its the =+16V/-16V power supply to the audio amp assembly board.
Cheapskates !
Unless there was a component change on that board it would not be something I would do.
Cheapskates !
Unless there was a component change on that board it would not be something I would do.
As I said, it's likely the bean counters. Most any consumer electronics that are produced for more than 5 years straight are lucky to make it through without some changes to increase profit. You can see this in items just like the T100 that started production in the 70's and ran into the 80's. Corporate priorities started to shift. Does this $2 part really make enough difference that people won't notice that we replaced it with a $1 part? Or maybe leave it out completely? IMHO you have a better chance of getting better built gear if you stick to 70's production...even though it may need some rebuilding.
Couldn't agree more its a shame when engineering quality and standards are profit driven to "improve " shareholder profits its becoming a downward spiral to cheap-very cheap production and "throwaway" after using for 6 months .
Time they got some engineers on their boards
Time they got some engineers on their boards
Thanks John, it was just what I was thinking about. I am planning to put those caps in place as they were in the '70s. As I have no limit budget for refurbishing, I think also to ad some MKP for decoupling as well as some high-quality caps on the audio stage in and out. This tuner sounds too good.
The thing is that it's still a good solid piece..it just needs a little help being all it can be. Sounds like you've run it enough to know how it behaves and if there's anything wrong or working poorly. That's a start. The next step is to figure out how far you may want to go with any work that you do...anywhere from just straight parts replacement to all out modification. This is very much like any collectible item..especially cars. How much do you want to keep as original? If you intend to hang on to this tuner, you may not be as concerned with resale value...and maybe a little more interested in going further with the work you do that could help take it through the last 5% or 10% of sound quality. Oh yeah...good deal on joining the FMTuner board. If there's anywhere on the internet that you can find people who are knowledgeable with that item, that's the place.
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I question this narrative. The bean counters don't have the expertise or the authority to substitute two caps for four, or a $1 part for a $2 part. Some engineer did that: no doubt under pressure, but it wasn't a bean counter acting alone.
Not a technician, but perhaps there was no measurable difference (or perhaps better without additional filtering)? Accuphase doesn't strike me as a company that would skimp on quality parts.