Technics SU-610, one channel down?...

[T i m]

Hi all,

Chatting to a mate the other day and in passing mentioned his old
Technics SU-610 amp, seems to have lost one channel and might I be
able to fix it (I\'ve just fixed a car battery charger for him). ;-)

He said if he turns the balance fully to that channel and the volume
fully up, he can just hear something from that speaker.

I\'ve suggested he try some tests ... actioning all the switches,
swapping the input leads over L/R, trying a different input, checking
the speaker connections / swapping the speakers, trying the headphone
socket etc and to let me know the outcome.

If it proves to be faulty and it comes to me, I\'ve picked up one of
those PC USB scopes (It was bought by my mate for his PC shop but
mainly used by me there ... and he\'s not used it since he retired) and
so I just need a signal source (any simple sine wave generator kits
out there?), the schematic (got) and I\'m good to go.

The schematic looks pretty simple (even for me <g>) but I\'m guessing
it\'s likely to be the main hybrid amp module, an SVI3102B and I see
they are still available for not a lot of money (new / used).

Along with the basic tone generator question, does anyone know this
model and is aware of any \'typical\' fault causes / weaknesses / mods
please?

Cheers, T i m

 

[legg]

On Sat, 31 Oct 2020 13:51:04 +0000, T i m <news@spaced.me.uk> wrote:

Hi all,

Chatting to a mate the other day and in passing mentioned his old
Technics SU-610 amp, seems to have lost one channel and might I be
able to fix it (I\'ve just fixed a car battery charger for him). ;-)

He said if he turns the balance fully to that channel and the volume
fully up, he can just hear something from that speaker.

I\'ve suggested he try some tests ... actioning all the switches,
swapping the input leads over L/R, trying a different input, checking
the speaker connections / swapping the speakers, trying the headphone
socket etc and to let me know the outcome.

If it proves to be faulty and it comes to me, I\'ve picked up one of
those PC USB scopes (It was bought by my mate for his PC shop but
mainly used by me there ... and he\'s not used it since he retired) and
so I just need a signal source (any simple sine wave generator kits
out there?), the schematic (got) and I\'m good to go.

The schematic looks pretty simple (even for me <g>) but I\'m guessing
it\'s likely to be the main hybrid amp module, an SVI3102B and I see
they are still available for not a lot of money (new / used).

Along with the basic tone generator question, does anyone know this
model and is aware of any \'typical\' fault causes / weaknesses / mods
please?

Cheers, T i m

switch/connector solder joints.

RL

 

[John-Del]

On Saturday, October 31, 2020 at 9:51:07 AM UTC-4, T i m wrote:

Hi all,

Chatting to a mate the other day and in passing mentioned his old
Technics SU-610 amp, seems to have lost one channel and might I be
able to fix it (I\'ve just fixed a car battery charger for him). ;-)

He said if he turns the balance fully to that channel and the volume
fully up, he can just hear something from that speaker.

I\'ve suggested he try some tests ... actioning all the switches,
swapping the input leads over L/R, trying a different input, checking
the speaker connections / swapping the speakers, trying the headphone
socket etc and to let me know the outcome.

If it proves to be faulty and it comes to me, I\'ve picked up one of
those PC USB scopes (It was bought by my mate for his PC shop but
mainly used by me there ... and he\'s not used it since he retired) and
so I just need a signal source (any simple sine wave generator kits
out there?), the schematic (got) and I\'m good to go.

The schematic looks pretty simple (even for me <g>) but I\'m guessing
it\'s likely to be the main hybrid amp module, an SVI3102B and I see
they are still available for not a lot of money (new / used).

Along with the basic tone generator question, does anyone know this
model and is aware of any \'typical\' fault causes / weaknesses / mods
please?

Cheers, T i m

I can\'t tell you how many of those came in over the years with cranky switches, either the rotating or sliding kind. Yes, by all means have him manipulate them or test those first if it shows up. If it responds, clean them accordingly.

The good news is that a stereo amp with one weird channel out of two identical channels is one of the easier things to troubleshoot in the consumer electronics world.

 

[Edward Hernandez]

On Saturday, October 31, 2020 at 12:44:09 PM UTC-5, John-Del wrote:

On Saturday, October 31, 2020 at 9:51:07 AM UTC-4, T i m wrote:
Hi all,

Chatting to a mate the other day and in passing mentioned his old
Technics SU-610 amp, seems to have lost one channel and might I be
able to fix it (I\'ve just fixed a car battery charger for him). ;-)

He said if he turns the balance fully to that channel and the volume
fully up, he can just hear something from that speaker.

I\'ve suggested he try some tests ... actioning all the switches,
swapping the input leads over L/R, trying a different input, checking
the speaker connections / swapping the speakers, trying the headphone
socket etc and to let me know the outcome.

If it proves to be faulty and it comes to me, I\'ve picked up one of
those PC USB scopes (It was bought by my mate for his PC shop but
mainly used by me there ... and he\'s not used it since he retired) and
so I just need a signal source (any simple sine wave generator kits
out there?), the schematic (got) and I\'m good to go.

The schematic looks pretty simple (even for me <g>) but I\'m guessing
it\'s likely to be the main hybrid amp module, an SVI3102B and I see
they are still available for not a lot of money (new / used).

Along with the basic tone generator question, does anyone know this
model and is aware of any \'typical\' fault causes / weaknesses / mods
please?

Cheers, T i m

I can\'t tell you how many of those came in over the years with cranky switches, either the rotating or sliding kind. Yes, by all means have him manipulate them or test those first if it shows up. If it responds, clean them accordingly.

The good news is that a stereo amp with one weird channel out of two identical channels is one of the easier things to troubleshoot in the consumer electronics world.

Great reply JD. No toxic or smart alec remarks. Keep this up! You just might win.

 

[Fox\'s Mercantile]

On 11/1/20 11:27 AM, Edward Hernandez wrote:
> No toxic or smart alec remarks.

Piss off charger boy.


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[T i m]

On Sat, 31 Oct 2020 10:44:05 -0700 (PDT), John-Del <ohger1s@gmail.com>
wrote:

<snip>

I can\'t tell you how many of those came in over the years with cranky switches, either the rotating or sliding kind. Yes, by all means have him manipulate them or test those first if it shows up.

He was away till just earlier and said he tried using a different
input and it worked, but didn\'t mention if he\'d tried going back to
the original ... (like I would have done).

For some people, as long as it\'s working they don\'t care about
anything else. ;-(


>If it responds, clean them accordingly.

Yeah, that would have been my next step, get some switch cleaner /
Elecrolube in them. ;-)

The good news is that a stereo amp with one weird channel out of two identical channels is one of the easier things to troubleshoot in the consumer electronics world.

Yeah, and this one looked pretty simple. ;-(

At least I\'ve now got myself a simple PC scope:

https://www.hantek.eu/dso-6022be.html

.... and have found it\'s also supported under Linux:

https://github.com/OpenHantek/openhantek

.... and found a mod that upgrades it to be AC coupling:

https://github.com/OpenHantek/OpenHantek6022/blob/master/docs/HANTEK6022_AC_Modification.pdf

The only thing I haven\'t worked out is if the default is DC after the
mod is applied as I don\'t think the factory software had the soft
switch and the Windows version of OpenHantek doesn\'t work on W10 on
the same PC when running Linux Mint (video errors, can\'t form the
actual scope screen display).

Cheers, T i m

 

[Edward Hernandez]

Where is Pony pete? He is better at this than you. You\'re like a caveman who knows a little about electronics. \"41 Years! I fix chargers!\" lol.

 

[Kenneth P. Farrell]

On Sun, 1 Nov 2020 09:27:22 -0800 (PST) the anus of Edward Hernandez <dtgamer99@gmail.com> sputtered:

Great reply JD. No toxic or smart alec remarks. Keep this up! You just
might win.

Stop being such a troll and go away. You got useful advice at the outset
on your charger in this group. Now you are simply acting like a spoiled
child who was told \"no candy before dinner\" by Mom & Dad when you really
wanted some candy.

 

[Edward H.]

On Sunday, November 1, 2020 at 2:04:19 PM UTC-6, Fox\'s Mercantile wrote:

On 11/1/20 11:27 AM, Edward Hernandez wrote:
No toxic or smart alec remarks.
Piss off charger boy.


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

Why do you keep creating fake names? It\'s pretty obvious. You are using the same words repeatedly. I told you you weren\'t as good as pony pete. Thanks for the effort you are making! hhahah!

 

[Fox\'s Mercantile]

On 11/2/20 9:19 AM, Edward H. wrote:
> Why do you keep creating fake names?

You\'re delusional. I have never used a fake name.


--
\"I am a river to my people.\"
Jeff-1.0
WA6FWi
http:foxsmercantile.com

 

[Edward H.]

On Monday, November 2, 2020 at 1:15:45 PM UTC-6, Enema man Fox Comics queeffed:

> You\'re delusional. I have never used a fake name.

Let\'s see what the comic man is up to. You\'re responding to my posts. Good work. Keep going.