"Pencil Tube", Battery Powered Phono Preamp

stellavox · 07:33 PM

Fiinally selling off a few projects that have been hanging around for a while.

First one is a phono preamp built using 4 pencil tubes (2X 6111 and 2X 6112) it's in the little grey box with input/output RCA's and a switch to select RIAA or NAB (tape EQ) - NAB position is NOT hooked up. It sits on top of a black box which houses a 12 volt battery, charger and HV inverter to supply the B+. The separate large wall wart plugs into the side of the black box and charges the battery. Just checked that a full charge supplies the preamp for around 4 hours. Gain is 40dB - fine for MM cartridges. Trace on the scope is a sweep from 20hz to 20Khz with the preamp fed from an inverse RIAA box. response is within 1/2dB over that range. Input impedance is 47K. Schematic included.

Selling as I don't have a TT anymore. Price $65 plus shipping.

THANKS

(hope the pic comes through - I'm new to this[IMG]

[/IMG]

neatokino · 21st December 2010, 05:08 AM

Hi-- is this still for sale? I'd like to buy it if it's still available. thanks!

stellavox · 21st December 2010, 11:26 AM

Closes in 2 hours Ebay

11th December 2010, 07:30 PM	#1
stellavox diyAudio Member Join Date: Jan 2007 Location: Oneonta, NY; USA	"Pencil Tube", Battery Powered Phono Preamp Fiinally selling off a few projects that have been hanging around for a while. First one is a phono preamp built using 4 pencil tubes (2X 6111 and 2X 6112) it's in the little grey box with input/output RCA's and a switch to select RIAA or NAB (tape EQ) - NAB position is NOT hooked up. It sits on top of a black box which houses a 12 volt battery, charger and HV inverter to supply the B+. The separate large wall wart plugs into the side of the black box and charges the battery. Just checked that a full charge supplies the preamp for around 4 hours. Gain is 40dB - fine for MM cartridges. Trace on the scope is a sweep from 20hz to 20Khz with the preamp fed from an inverse RIAA box. response is within 1/2dB over that range. Input impedance is 47K. Schematic included. Selling as I don't have a TT anymore. Price $65 plus shipping. THANKS (hope the pic comes through - I'm new to this[IMG][/IMG] Last edited by stellavox; 11th December 2010 at 07:33 PM.

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
"Wineclone" Battery-powered Amplifier SUMMER SALE! $50 off!	gripracer	Swap Meet	19	31st December 2010 09:56 PM
D.I.Y. "Duplex" 2sk369 jfet mm phono preamp	doggy	Analogue Source	6	26th September 2006 08:23 AM
FS: Unfinished phono preamp w/ "audiophile" parts	needtubes	Swap Meet	1	5th July 2005 09:50 PM
Newbie wants to build a "GainClone-Like" 5.1 Channel Battery Powered Amplifier	captain	Chip Amps	7	15th October 2004 12:35 PM
"Zen" tube phono-amps ?	peted	Pass Labs	2	8th March 2001 12:51 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

21st December 2010, 05:08 AM	#2
neatokino diyAudio Member Join Date: Nov 2010	Hi-- is this still for sale? I'd like to buy it if it's still available. thanks!

21st December 2010, 11:26 AM	#3
stellavox diyAudio Member Join Date: Jan 2007 Location: Oneonta, NY; USA	Closes in 2 hours Ebay

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)