thr light in pcl82

death · 22nd April 2012, 07:09 AM

hi there
recently i tried a pcl82 se amp. the problem is with the heater.
i supply the heater with 15 volts ac of a 2x7.5 V,3A transformer.the no load voltage of the trans is about 17volts ac. by my knowledge this tube's heater is a 300mA at 16 volts. it works but when i power on the tube, i see a yellow light shining from the junction of the heater in the tube. it shines for just a second .i want to know if this is bad for the tube.?
my tube is telefunken and is not used so i think maybe the power supply is not good for this kind of tube.or maybe its because of the tube !?

v4lve lover · 22nd April 2012, 09:49 AM

dont worry its pretty common .
PCL82 are there in abundance if it breaks replace it .
maybye add an NTC ?

v4lve .

Shoog · 22nd April 2012, 10:07 AM

This type of power on surge is very common on old valves. There is no problem and the valve will give normal service.

Shoog

death · 27th April 2012, 07:41 PM

hi
thank you all
so i think its safe to continue .
last night i was reading "pcc88" datasheet and it said that there is a need for current limitig resistor because of the starting current is high when the filament is cold. i think the ntc may works.

22nd April 2012, 07:09 AM	#1
death diyAudio Member Join Date: May 2011 Location: tehran	thr light in pcl82 hi there recently i tried a pcl82 se amp. the problem is with the heater. i supply the heater with 15 volts ac of a 2x7.5 V,3A transformer.the no load voltage of the trans is about 17volts ac. by my knowledge this tube's heater is a 300mA at 16 volts. it works but when i power on the tube, i see a yellow light shining from the junction of the heater in the tube. it shines for just a second .i want to know if this is bad for the tube.? my tube is telefunken and is not used so i think maybe the power supply is not good for this kind of tube.or maybe its because of the tube !?

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
k-502/k-12m vs. Model 1 pcl82	webelo	Tubes / Valves	3	20th October 2007 04:33 AM
PCL82 SE Tube Amplifier Kit	savakovacevic	Tubes / Valves	4	28th January 2006 09:41 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

22nd April 2012, 09:49 AM	#2
v4lve lover diyAudio Member Join Date: Aug 2010 Location: Near Eindhoven, the sanctum of the pentode. and among that other things.	dont worry its pretty common . PCL82 are there in abundance if it breaks replace it . maybye add an NTC ? v4lve .

22nd April 2012, 10:07 AM	#3
Shoog diyAudio Member Join Date: Aug 2002 Location: Eire	This type of power on surge is very common on old valves. There is no problem and the valve will give normal service. Shoog

27th April 2012, 07:41 PM	#4
death diyAudio Member Join Date: May 2011 Location: tehran	hi thank you all so i think its safe to continue . last night i was reading "pcc88" datasheet and it said that there is a need for current limitig resistor because of the starting current is high when the filament is cold. i think the ntc may works.