Hello
Thank you for such a great site.
I have 2 Amplifiers that are exhibiting the same problem
Sony TA-F808ES & TA-F555esR
After about 10 minutes of use the right channel cuts out on the esR & the left channel cuts out on the 808ES. It's random. Sometimes the amps will work for 10 or so minutes, then the sound becomes fuzzy and begins to deteriorate completely. I have pushed "source direct" on the esR and the sound comes back in both channels but heavily distorted. I have read before that Sony equipment has weak solder joints/traces
Any Thoughts?
Paul
Thank you for such a great site.
I have 2 Amplifiers that are exhibiting the same problem
Sony TA-F808ES & TA-F555esR
After about 10 minutes of use the right channel cuts out on the esR & the left channel cuts out on the 808ES. It's random. Sometimes the amps will work for 10 or so minutes, then the sound becomes fuzzy and begins to deteriorate completely. I have pushed "source direct" on the esR and the sound comes back in both channels but heavily distorted. I have read before that Sony equipment has weak solder joints/traces
Any Thoughts?
Paul
It looks like a thermal issue or bad contact, bad soldering.
1) spray cool air to the transistors one by one, from drivers to input diff. to locate the culprit.
2) measure the supply voltages when normal and when not normal.
3) check for bad joints, re-soldering all will help.
1) spray cool air to the transistors one by one, from drivers to input diff. to locate the culprit.
2) measure the supply voltages when normal and when not normal.
3) check for bad joints, re-soldering all will help.
Both amps have speaker output relays. Often over time, the relay contacts get oxidized and hinder the output. Next time you get the issue you describe, lightly tap on the relay and see if the issue changes. If it does, then the contacts need to be cleaned.After you report I'll tell you my way of doing it.
Cheers
Cheers
I've had very similar problems with a Sony TA-F500ES that I've owned from new. The issue is almost certainly due to 'bad contacts' as Alexchoi already suggested, specifically in one (and likely more) of the following locations:
Protection relay contacts dirty
Speaker selection switch contacts dirty
Input selection switch contacts dirty
(In the TA-F500ES) The protection relay is relatively straightforward to replace, but in my case only 'solved' the problem for a month or so.
The speaker selection switch in the TA-F500 is a remote rotary control, so the rotary control on the face of the amp only actuates a sliding metal strip, which carries the motion back to the 'real' pcb mounted slide switch at the back of the amp. The actual contacts are 'buried' deep within the slide switch on the pcb - cleaning them requires desoldering, and complete disassembly of the slide switch... no amount of deoxit spraying will clean them properly in situ (I've tried). You can see the type of slide switch I'm referring to, on Page 9 of the service manual for your TA-F808ES (free on hifiengine.com). In my case, this was also relatively straightforward, once I'd understood the issue, but again, only partially 'solved' the problem.
The third set of contacts which were involved in my case, were within the input selection switch, which is again a rotary slide switch, but in this case without the remote bowden slide parts - it is however somewhat similar to the above slide switch in that it is also directly pcb mounted, with the contacts completely 'buried' within. The bad news was, it's a lot more work to access. Again, it had to be completely desoldered from the pcb (that's 32 solder joints, for one switch), stripped, and cleaned properly. The photo shows the switch I mean.
I don't know which of these types of switches you have, but I'd put money on the problem being due to one or more of them if they're present (... both your amps are from the same era as the TA-F500ES, so it's likely). On the plus side - of the various ES models I've worked on from the same era I've never found a single bad solder joint.
Protection relay contacts dirty
Speaker selection switch contacts dirty
Input selection switch contacts dirty
(In the TA-F500ES) The protection relay is relatively straightforward to replace, but in my case only 'solved' the problem for a month or so.
The speaker selection switch in the TA-F500 is a remote rotary control, so the rotary control on the face of the amp only actuates a sliding metal strip, which carries the motion back to the 'real' pcb mounted slide switch at the back of the amp. The actual contacts are 'buried' deep within the slide switch on the pcb - cleaning them requires desoldering, and complete disassembly of the slide switch... no amount of deoxit spraying will clean them properly in situ (I've tried). You can see the type of slide switch I'm referring to, on Page 9 of the service manual for your TA-F808ES (free on hifiengine.com). In my case, this was also relatively straightforward, once I'd understood the issue, but again, only partially 'solved' the problem.
The third set of contacts which were involved in my case, were within the input selection switch, which is again a rotary slide switch, but in this case without the remote bowden slide parts - it is however somewhat similar to the above slide switch in that it is also directly pcb mounted, with the contacts completely 'buried' within. The bad news was, it's a lot more work to access. Again, it had to be completely desoldered from the pcb (that's 32 solder joints, for one switch), stripped, and cleaned properly. The photo shows the switch I mean.
I don't know which of these types of switches you have, but I'd put money on the problem being due to one or more of them if they're present (... both your amps are from the same era as the TA-F500ES, so it's likely). On the plus side - of the various ES models I've worked on from the same era I've never found a single bad solder joint.
From what I’m experiencing, some of the Inputs are having issues. On the esR inputs 2 and 3 have a problem after 10 minutes. The amp has to be cool for it to work for 10 minutes. On input 1 there is no issue and the esR was used for an hour. Thankfully at least this input works reliably. I have not used deoxit, but did exercise the input switch a little. Since it’s works in Tape 1 input, I’ll leave that amp alone and hopefully it stays ok. I’m good with it working in 1 tape input. The aux input has been working as well. It’s ok for now. The Sony TC-K870ES is plugged into Tape 1 & an Onkyo DP-X1 is plugged into aux.
The 808 is apart and no inputs work reliably. That has a motorized switch
The 808 is apart and no inputs work reliably. That has a motorized switch
for the TA-F555esR
in the following link,
from the images, one can get the idea of the faults .
Google Translate
dodgy, bad joints..
especially the 100r 1/2w resistor on the power rails,
check their values, ( R324, R325, R374, R375 ),
( R322, R372, 27 1/2w),
( R329, R379, 68 1/2w),
check those resistors which had a dark grey background in the schematic.
I have two TA-F333esr which had the same issue once before.
in the following link,
from the images, one can get the idea of the faults .
Google Translate
dodgy, bad joints..
especially the 100r 1/2w resistor on the power rails,
check their values, ( R324, R325, R374, R375 ),
( R322, R372, 27 1/2w),
( R329, R379, 68 1/2w),
check those resistors which had a dark grey background in the schematic.
I have two TA-F333esr which had the same issue once before.
Last edited:
For the TA-F808ES - I don't think you can avoid dismantling and cleaning the several remote slide switchs shown in the manual. As an example, a similar set of slide switch contacts, from my TA-F500ES, looked like this when I opened one of the switches a year or so back (for similar problems). They are impossible to access with Deoxit without full dismantling - but they are also delicate, and very difficult to replace. Be sure to note the exact positions of the contacts...
One other point to check in the 808 would be all of the fusible resistors, they can be problematic as well after so many years.
One other point to check in the 808 would be all of the fusible resistors, they can be problematic as well after so many years.
amendment
the schematic I downloaded was TA-F555es, not TA-F555esr.
there may be differences in the resistor numbers in the schematics,
but can take it as reference of the faults.
the schematic I downloaded was TA-F555es, not TA-F555esr.
there may be differences in the resistor numbers in the schematics,
but can take it as reference of the faults.
Thank you for your help and responses. I have taken apart the 808, and now have the input board on the bench. I noticed the silver contacts sleeve that moves Has some corrosion on it. You can see the pictures attached. Also the gold plated contacts are tarnished. Probably a good idea to replace all the resistors on this board like you guys were saying. What is the recommendation on rebuilding the switches to clean the silver sleeve?
There was a good amount of dust everywhere.
There was a good amount of dust everywhere.
@PaulRobert - in your first photo, there are 3 (blue) rotary switches shown near the front of the main amp chassis - these are all connected via 'slides' to the actual pcb mounted switches further back in your amp. It's the pcb mounted parts that have the contacts - 2 of them are shown in your 3rd. photo (looks like S102 & S103). The 3rd. may be on the EQ board.
Your 5th photo shows one of the switch 'slides' - it's simply a narrow strip of (spring?) steel sliding back & forth in a plastic sheath (translating the rotary motion of the front panel control, to a linear slide motion for the pcb mounted switch). Slight corrosion on the slide shouldn't be an issue as long as it's not extreme.
As an illustration - the following pics are the exact same type of remote slide switch as you seem to have (S102 & S103 on the input board) - as I dismantled & cleaned mine. The 6th. pic is the actual contacts - yours will likely be in a similar condition.
Finally, to access the contacts, once you've desoldered the entire switch from the pcb, you'll need to manually bend the small metal retaining tabs back (I used long nose pliers) - then you can remove the contacts, slide, etc. _ BEING VERY CAREFUL TO NOTE POSITIONS, AND NOT BEND ANYTHING - I repeat, the small brass sliders are very delicate. Gently lift the black plastic slide (shown in my photo #5) away from the pins, don't slide it off the end... then the brass contacts will hopefully remain in position as in photo #6.
For what it's worth - if you come across any of the rotary switches such as in the photo I put in post #4 a couple of weeks ago - the contact arrangement is exactly the same.
On the resistors - for the TA-F808ES - I wouldn't touch any of them on the input board (why ?). The key ones to check, throughout the amp, are the 'fusible' resistors - they're all shown in the schematics (see page 11 of the SM for the symbol if needed). I didn't check the TA-F555ESR manual, but if that uses fusibles, then it's worth checking those also.
Your 5th photo shows one of the switch 'slides' - it's simply a narrow strip of (spring?) steel sliding back & forth in a plastic sheath (translating the rotary motion of the front panel control, to a linear slide motion for the pcb mounted switch). Slight corrosion on the slide shouldn't be an issue as long as it's not extreme.
As an illustration - the following pics are the exact same type of remote slide switch as you seem to have (S102 & S103 on the input board) - as I dismantled & cleaned mine. The 6th. pic is the actual contacts - yours will likely be in a similar condition.
Finally, to access the contacts, once you've desoldered the entire switch from the pcb, you'll need to manually bend the small metal retaining tabs back (I used long nose pliers) - then you can remove the contacts, slide, etc. _ BEING VERY CAREFUL TO NOTE POSITIONS, AND NOT BEND ANYTHING - I repeat, the small brass sliders are very delicate. Gently lift the black plastic slide (shown in my photo #5) away from the pins, don't slide it off the end... then the brass contacts will hopefully remain in position as in photo #6.
For what it's worth - if you come across any of the rotary switches such as in the photo I put in post #4 a couple of weeks ago - the contact arrangement is exactly the same.
On the resistors - for the TA-F808ES - I wouldn't touch any of them on the input board (why ?). The key ones to check, throughout the amp, are the 'fusible' resistors - they're all shown in the schematics (see page 11 of the SM for the symbol if needed). I didn't check the TA-F555ESR manual, but if that uses fusibles, then it's worth checking those also.
Thank you for the recommendation where to go to find the issue. I pulled apart the first switch assy on the Sony TA-F808ES. I am pacing myself on this project and have a bit more to go. I am usually working with cassette decks. 2 More switches to go
I got all 3 slider assemblies cleaned. Will go into the source direct and muting switch to clean them up as well. I suspect the problem is not isolated to one area, rather many.
All three slider assemblies have been soldered back onto the respective boards. I was looking at the motorized input selector assembly, because I’ve known before that Sony uses rotary type connections in their equipment, and that was a place to find failures. After opening up the assembly it was clear they were many failures in this 808. The connections are very delicate and precise. A clear decision by Sony’s design team. Quite complicated. But fixable. There are a few random places with broken solder.
You can see how tarnished both left and right channel rotary encoders are
You can see how tarnished both left and right channel rotary encoders are
I found the same in the TA-F500ES after almost 35 yrs - new output relay, and all the remote slide contacts needed a good clean. I tried initially to avoid having to strip the slide switches, but I had to go back and do them in the end. Now it's back to its original '87 performance.
I know that this is an old thread by 1 year but FWIW, Yamaha CA-810 has the same affliction. The sliders are very similar and require complete disassembly to clean. I use fiberglass pens made just for this issue. The fiberglass fibers are great at removing the tarnish. No chemicals required.
Do you not find the fibreglass pens too agressive for the Silver alloy (?) plating ?
The last one I did, I just used Acetone on a cotton bud, it took a while but the slide surface came back to a clean shiny 'Silvery' finish.
Fiberglass Scratch Brush Pen - 3 Pack - Jewelry, Watch, Coin Cleaning, Electronic applications, Removing rust and corrosion https://a.co/d/Isabella Anderson,. There are many other sellers on other sites, web stores etc . These are twist operated to extend or retract the fibers. DO NOT TOUCH or handle fibers! This cause intense itching. Wear breathing protection as well if you are sensitive to irritants.