That'll Teach Me... (Chinese Valve Amp)
 

"Keith G" wrote in message
...


Why do you say 'That'll teach me'??

Disappointment at the failure, and sick realization that I couldn't really
send it back.
Darned thing sat there looking accusingly at me for months every time I went
into the "office".

Now the offers of help from a couple of the board members has improved my
outlook.


Like you could have bought a Border Patrol 300B amp (say) for anything
upwards of 4K:

http://www.users.globalnet.co.uk/~va...rPatrolAmp.htm

http://www.borderpatrol.co.uk/amprev.htm



No, but I could have bought a used Sugden Class A amp, for example?


...but chose the Chinaman for what - less than 400 quid instead? (You get
what you pay for in this life!! :-)

Anyway, I see you've had a couple of kind offers of help already - expect
to pay for some parts, needless to say...


Yes!

That'll Teach Me... (Chinese Valve Amp)
 

"Steve" wrote in message
...
Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in fixing the
amp, I've emailed them to arrange a consultation.

Steve


You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)

Iain

That'll Teach Me... (Chinese Valve Amp)
 

Iain Churches wrote:
"Steve" wrote in message
...

Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in fixing the
amp, I've emailed them to arrange a consultation.

Steve



You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Hmm, not too keen to do that :-)

http://hi-end.on9mart.com/products/a...8-photo_13.JPG

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)


One of the 680R 50W ali clad wirewounds in the 300b cathodes had gone
open circuit. Should be replaced tomorrow. Clipping in a 1k (didn't have
680R) it all seems to be ok, so think it was just a failed resistor.

I will give it a quick once over once the R is changed, I suspect that
voltages might be a tad high, dur to the mains being 240v at my place. I
notice the same amp has a mention on rat about killing rectifiers. Seems
ok at the moment.

It seems to drive 300bs hard, the good chan had 70v on its cathode,
which makes it 100ma current, and about 400v on the valve, so not for
mesh plates. It might get better with both chans pulling current though.

--
Nick

That'll Teach Me... (Chinese Valve Amp)
 

You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)

Iain


I visited Nick on Sunday. It took him just a few minutes to identify a dodgy
resistor which he is going to replace for me in the next couple of days.

In very good hands indeed.

Steve

That'll Teach Me... (Chinese Valve Amp)
 

Nick Gorham wrote:
Iain Churches wrote:
"Steve" wrote in message
...

Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in
fixing the amp, I've emailed them to arrange a consultation.

Steve



You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Hmm, not too keen to do that :-)

http://hi-end.on9mart.com/products/a...8-photo_13.JPG

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)


One of the 680R 50W ali clad wirewounds in the 300b cathodes had gone
open circuit. Should be replaced tomorrow. Clipping in a 1k (didn't
have 680R) it all seems to be ok, so think it was just a failed
resistor.
I will give it a quick once over once the R is changed, I suspect that
voltages might be a tad high, dur to the mains being 240v at my
place. I notice the same amp has a mention on rat about killing
rectifiers. Seems ok at the moment.

It seems to drive 300bs hard, the good chan had 70v on its cathode,
which makes it 100ma current, and about 400v on the valve, so not
for mesh plates. It might get better with both chans pulling current
though.

Excellent news & work.
It even looks quite well-constructed from the photo.
All the best,
Martin.

That'll Teach Me... (Chinese Valve Amp)
 

"Martin Crossley" wrote in message
...
Nick Gorham wrote:
Iain Churches wrote:
"Steve" wrote in message
...

Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in
fixing the amp, I've emailed them to arrange a consultation.

Steve



You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Hmm, not too keen to do that :-)

http://hi-end.on9mart.com/products/a...8-photo_13.JPG

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)


One of the 680R 50W ali clad wirewounds in the 300b cathodes had gone
open circuit. Should be replaced tomorrow. Clipping in a 1k (didn't
have 680R) it all seems to be ok, so think it was just a failed
resistor.
I will give it a quick once over once the R is changed, I suspect
that
voltages might be a tad high, dur to the mains being 240v at my
place. I notice the same amp has a mention on rat about killing
rectifiers. Seems ok at the moment.

It seems to drive 300bs hard, the good chan had 70v on its cathode,
which makes it 100ma current, and about 400v on the valve, so not
for mesh plates. It might get better with both chans pulling current
though.

Excellent news & work.
It even looks quite well-constructed from the photo.


One thing people seem to overlook is that, disregarding the innards
entirely for the moment, you couldn't get the *casework* for anything
like the price of these amps and I believe this particular amp even
comes with a remote control?

That'll Teach Me... (Chinese Valve Amp)
 

"Nick Gorham" wrote in message
...
Iain Churches wrote:
"Steve" wrote in message
...

Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in fixing
the amp, I've emailed them to arrange a consultation.

Steve



You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Hmm, not too keen to do that :-)

http://hi-end.on9mart.com/products/a...8-photo_13.JPG

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)


One of the 680R 50W ali clad wirewounds in the 300b cathodes had gone
open circuit. Should be replaced tomorrow. Clipping in a 1k (didn't
have 680R) it all seems to be ok, so think it was just a failed
resistor.

I will give it a quick once over once the R is changed, I suspect that
voltages might be a tad high, dur to the mains being 240v at my place.
I notice the same amp has a mention on rat about killing rectifiers.
Seems ok at the moment.

It seems to drive 300bs hard, the good chan had 70v on its cathode,
which makes it 100ma current, and about 400v on the valve, so not
for mesh plates. It might get better with both chans pulling current
though.


I would be interested in your opinion on the *sound quality* when you've
got it bashed into shape, Nick!

That'll Teach Me... (Chinese Valve Amp)
 

"Steve" wrote in message
...

You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.

Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)

Iain


I visited Nick on Sunday. It took him just a few minutes to identify a
dodgy
resistor


Jammy sod....

:-)

That'll Teach Me... (Chinese Valve Amp)
 

In article ,
Keith G wrote:
One thing people seem to overlook is that, disregarding the innards
entirely for the moment, you couldn't get the *casework* for anything
like the price of these amps and I believe this particular amp even
comes with a remote control?

Same applies to any mass produced piece of audio gear.

--
*He who dies with the most toys is, nonetheless, dead.

Dave Plowman London SW
To e-mail, change noise into sound.

That'll Teach Me... (Chinese Valve Amp)
 

Keith G wrote:
"Nick Gorham" wrote in message
...

Iain Churches wrote:

"Steve" wrote in message
...


Thanks to you all for advice/support.

In particular, thanks to Martin and Nick for offers of help in fixing
the amp, I've emailed them to arrange a consultation.

Steve



You seem to be in very good hands, Steve:-)
Try to get one of these two gents to trace out the
circuit for you. It might be useful in the future.


Hmm, not too keen to do that :-)

http://hi-end.on9mart.com/products/a...8-photo_13.JPG


Oh, and come back and tell us how it all
turned out. The whole world loves a happy ending:-)


One of the 680R 50W ali clad wirewounds in the 300b cathodes had gone
open circuit. Should be replaced tomorrow. Clipping in a 1k (didn't
have 680R) it all seems to be ok, so think it was just a failed
resistor.

I will give it a quick once over once the R is changed, I suspect that
voltages might be a tad high, dur to the mains being 240v at my place.
I notice the same amp has a mention on rat about killing rectifiers.
Seems ok at the moment.

It seems to drive 300bs hard, the good chan had 70v on its cathode,
which makes it 100ma current, and about 400v on the valve, so not
for mesh plates. It might get better with both chans pulling current
though.



I would be interested in your opinion on the *sound quality* when you've
got it bashed into shape, Nick!





Hopefully that should be tonight. If RS have been as prompt as normal.

--
Nick