Hi,

My Laney VC50 has developed a problem. Mains power going in, HT fuse
okay, LEDs on front panel light up, but valve heater bases refuse to
glow. And when switching on standby - nothing, except great amounts of
despondency of course.

Any thoughts/help/counselling very welcome!

And ultimately, I guess can anyone point me to a good amp tech if it
comes to it?

TIA

Tim

"Tim Hacker"  wrote in message 
news:ce74bbfd-43bc-42f3-a406-0be8f1daad33@m11g2000vbl.googlegroups.com...
> Hi,
>
> My Laney VC50 has developed a problem. Mains power going in, HT fuse
> okay, LEDs on front panel light up, but valve heater bases refuse to
> glow. And when switching on standby - nothing, except great amounts of
> despondency of course.
>
> Any thoughts/help/counselling very welcome!
>
> And ultimately, I guess can anyone point me to a good amp tech if it
> comes to it?
>
> TIA
>
> Tim

Heater circuit probably has fuses on the PCB. Check those. Requires chassis 
to be removed.

Andrew(lefty)

"Andrew\(lefty\)"  wrote in
news:RbRsm.80519$OO7.48152@text.news.virginmedia.com: 

> 
> "Tim Hacker"  wrote in message 
> news:ce74bbfd-43bc-42f3-a406-0be8f1daad33
@m11g2000vbl.googlegroups.com.
> .. 
>> Hi,
>>
>> My Laney VC50 has developed a problem. Mains power going in, HT fuse
>> okay, LEDs on front panel light up, but valve heater bases refuse to
>> glow. And when switching on standby - nothing, except great amounts
>> of despondency of course.
>>
>> Any thoughts/help/counselling very welcome!
>>
>> And ultimately, I guess can anyone point me to a good amp tech if it
>> comes to it?
>>
>> TIA
>>
>> Tim
> 
> Heater circuit probably has fuses on the PCB. Check those. Requires
> chassis to be removed.


There is a 5A heater fuse that hooks to the grey wire on the main 
transformer (probably on the supply PCB).
 I used to have a schematic for the VC50 but I can't locate it at the 
moment but there's a copy here:

http://tremolo.elektroda.net/Firmowe/LANEY/VC50.pdf

If the heater fuse has gone, chances are one of the valves has popped it
so take them all out after you replace the fuse and power up. Then put 
in the two EL34s and 12AX7 phase splitter and switch on again. Keep 
adding valves until either you locate the faulty one or all are in and
the amp is running.

"Tim Hacker"  wrote in message 
news:ce74bbfd-43bc-42f3-a406-0be8f1daad33@m11g2000vbl.googlegroups.com...
> Hi,
>
> My Laney VC50 has developed a problem. Mains power going in, HT fuse
> okay, LEDs on front panel light up, but valve heater bases refuse to
> glow. And when switching on standby - nothing, except great amounts of
> despondency of course.
>
> Any thoughts/help/counselling very welcome!
>
> And ultimately, I guess can anyone point me to a good amp tech if it
> comes to it?

The ultimate amp tech/builder/guru is of course our Trev:
http://www.tipton-amps.co.uk/

George

...thank you guys, will try and seek out heater fuse - sounds a likely
culprit!

May still need the services of Mr Ridney

Cheers

Tim


On Sep 18, 9:02 pm, soupdragon  wrote:
> "Andrew\(lefty\)"  wrote innews:RbRsm.80519$OO7.48152@text.news.virginmedia.com:
>
>
>
> > "Tim Hacker"  wrote in message
> > news:ce74bbfd-43bc-42f3-a406-0be8f1daad33
>
> @m11g2000vbl.googlegroups.com.
>
>
>
>
>
> > ..
> >> Hi,
>
> >> My Laney VC50 has developed a problem. Mains power going in, HT fuse
> >> okay, LEDs on front panel light up, but valve heater bases refuse to
> >> glow. And when switching on standby - nothing, except great amounts
> >> of despondency of course.
>
> >> Any thoughts/help/counselling very welcome!
>
> >> And ultimately, I guess can anyone point me to a good amp tech if it
> >> comes to it?
>
> >> TIA
>
> >> Tim
>
> > Heater circuit probably has fuses on the PCB. Check those. Requires
> > chassis to be removed.
>
> There is a 5A heater fuse that hooks to the grey wire on the main
> transformer (probably on the supply PCB).
>  I used to have a schematic for the VC50 but I can't locate it at the
> moment but there's a copy here:
>
> http://tremolo.elektroda.net/Firmowe/LANEY/VC50.pdf
>
> If the heater fuse has gone, chances are one of the valves has popped it
> so take them all out after you replace the fuse and power up. Then put
> in the two EL34s and 12AX7 phase splitter and switch on again. Keep
> adding valves until either you locate the faulty one or all are in and
> the amp is running.

On Fri, 18 Sep 2009 20:02:13 +0000 (UTC), soupdragon 
wrote:

>"Andrew\(lefty\)"  wrote in
>news:RbRsm.80519$OO7.48152@text.news.virginmedia.com: 
>
>> 
>> "Tim Hacker"  wrote in message 
>> news:ce74bbfd-43bc-42f3-a406-0be8f1daad33
>@m11g2000vbl.googlegroups.com.
>> .. 
>>> Hi,
>>>
>>> My Laney VC50 has developed a problem. Mains power going in, HT fuse
>>> okay, LEDs on front panel light up, but valve heater bases refuse to
>>> glow. And when switching on standby - nothing, except great amounts
>>> of despondency of course.
>>>
>>> Any thoughts/help/counselling very welcome!
>>>
>>> And ultimately, I guess can anyone point me to a good amp tech if it
>>> comes to it?
>>>
>>> TIA
>>>
>>> Tim
>> 
>> Heater circuit probably has fuses on the PCB. Check those. Requires
>> chassis to be removed.
>
>
>There is a 5A heater fuse that hooks to the grey wire on the main 
>transformer (probably on the supply PCB).
> I used to have a schematic for the VC50 but I can't locate it at the 
>moment but there's a copy here:
>
>http://tremolo.elektroda.net/Firmowe/LANEY/VC50.pdf
>
>If the heater fuse has gone, chances are one of the valves has popped it
>so take them all out after you replace the fuse and power up. Then put 
>in the two EL34s and 12AX7 phase splitter and switch on again. Keep 
>adding valves until either you locate the faulty one or all are in and
>the amp is running.

I'm not sure if that sounds more like 'Beam me up Scotty" Or "Cut the
grey..Cut the Grey!"

Don't valves go in the same way as lightbulbs - you can see the break
in the coil?

Pete (who's skills end at wiring jack plugs)

wrote in message 
news:nh68b55804qgghi3u578psrbq8h3buckbr@4ax.com...
>
>
> On Fri, 18 Sep 2009 20:02:13 +0000 (UTC), soupdragon 
> wrote:
>
>>"Andrew\(lefty\)"  wrote in
>>news:RbRsm.80519$OO7.48152@text.news.virginmedia.com:
>>
>>>
>>> "Tim Hacker"  wrote in message
>>> news:ce74bbfd-43bc-42f3-a406-0be8f1daad33
>>@m11g2000vbl.googlegroups.com.
>>> ..
>>>> Hi,
>>>>
>>>> My Laney VC50 has developed a problem. Mains power going in, HT fuse
>>>> okay, LEDs on front panel light up, but valve heater bases refuse to
>>>> glow. And when switching on standby - nothing, except great amounts
>>>> of despondency of course.
>>>>
>>>> Any thoughts/help/counselling very welcome!
>>>>
>>>> And ultimately, I guess can anyone point me to a good amp tech if it
>>>> comes to it?
>>>>
>>>> TIA
>>>>
>>>> Tim
>>>
>>> Heater circuit probably has fuses on the PCB. Check those. Requires
>>> chassis to be removed.
>>
>>
>>There is a 5A heater fuse that hooks to the grey wire on the main
>>transformer (probably on the supply PCB).
>> I used to have a schematic for the VC50 but I can't locate it at the
>>moment but there's a copy here:
>>
>>http://tremolo.elektroda.net/Firmowe/LANEY/VC50.pdf
>>
>>If the heater fuse has gone, chances are one of the valves has popped it
>>so take them all out after you replace the fuse and power up. Then put
>>in the two EL34s and 12AX7 phase splitter and switch on again. Keep
>>adding valves until either you locate the faulty one or all are in and
>>the amp is running.
>
> I'm not sure if that sounds more like 'Beam me up Scotty" Or "Cut the
> grey..Cut the Grey!"
>
> Don't valves go in the same way as lightbulbs - you can see the break
> in the coil?
>
> Pete (who's skills end at wiring jack plugs)


The heater is enclosed in a metal tube called the cathode in all of the 
common gtr amp valves, so no, you'd be lucky to see the break in a heater 
unless it was below the cathode where the heater wire is bonded to a thicker 
wire.

Chris