For the past year, Ive been making regulated linear power supplies for my
own audio projects AND for sale to others. For most audio projects, a
regulated B+ is overkill, so Ive been installing a jumper across the
regulator section of my PC boards and making a few plain old low tech, saggy B+
supplies, and they have worked out great. Now that Im happy with them,
Ive decided to gear up for production on these and add them to my power
supply product line.

I have two versions. The €œhigh voltage€? model can easily power up to four
12AX7s with at least 300 V. The €œlow voltage€? supplies half the voltage
but double the current, so its ideal for subminiature and 6922/6DJ8 designs.
Each can supply up to 5 Watts of power and produces less than 10 mV p-p of
ripple when fully loaded. FR107 Fast recovery rectifiers are used, and has a
CR section filter included onboard. Jumper selectable for 120 / 240 VAC input.
Board dimensions are 3.8" x 2.5".

I have posted transfer curves and data tables on my website at
http://members.aol.com/ecc81.

The high voltage version (LDF5-320) has the following specifications;
* 357 Volts (minimum) output unloaded, with 110 / 220 VAC (low line) input
* 250 Volts (minimum) output at full load, with 110 / 220 VAC (low line) input
* Can supply up to 17 mA, at full load
* Height is less than 1.375" (fits in 1U rackmount chassis)

The low voltage version (LDF5-160) has the following specifications;
* 188 Volts (minimum) output unloaded, with 110 / 220 VAC (low line) input
* 120 Volts (minimum) output at full load, with 110 / 220 VAC (low line) input
* Can supply up to 35 mA, at full load
* Height is less than 1.5" (fits in 1U rackmount chassis)

Just to give you some idea of how to apply one of my power supplies to a
typical design, assume that you want to power a circuit that has a pair of
12AX7 tubes in it. You know that you want your B+ to be 300 V, and that the
circuit draws 6 mA. Refer to the transfer curve (on my website, and included
with the power supplies), and notice that when the line voltage is 115 VAC, the
power supply will provide about 335 V at 6 mA. So to drop the 35 V, externally
add a 5.6K Ohm 1/2 W dropping resistor followed by a 22 uF 450 capacitor and
youre DONE.

Im asking $32 each, plus shipping, for these power supplies.

OR, buy one LDF5-160 or LDF5-320, AND one of my linear regulated filament
supplies (PS6VA-6 or PS6VA-12), for $60 shipping included. (Shipping address
must be in the US48, offer good through September 30, 2003.)

And if you plan to scratch build a tube mic pre, buy one LDF5-160 or LDF5-320,
AND one PS6VA-48 (regulated phantom power supply) AND a linear regulated
filament supply (PS6VA-6 or PS6VA-12) for $90 shipping included. (Shipping
address must be in the US48, offer good through September 30, 2003.)

Sales can be prepaid by credit card through PayPal. If you have any additional
questions that my website cant answer, or if you want to buy some power
supplies, please respond BY EMAIL to , DO NOT POST. And
please include your shipping address in your email.

Regards,
Tom Mitchell
website - http://members.aol.com/ecc81
website - http://www.over-reactors.com

OvrReactor wrote:
For the past year, Ive been making regulated linear power supplies for my
own audio projects AND for sale to others. For most audio projects, a
regulated B+ is overkill, so Ive been installing a jumper across the
regulator section of my PC boards and making a few plain old low tech, saggy B+
supplies, and they have worked out great. Now that Im happy with them,
Ive decided to gear up for production on these and add them to my power
supply product line.
[...]

Neat! Good additions to your line. Fine for preamps, etc. or flea-power
PA's.

Are you contemplating any gutsier ones? (E.g. 350 v at 100 mA for things
like pp 6BQ5, 6V6, etc.)

Cheers,
Fred
--
+--------------------------------------------+
| Music: http://www3.telus.net/dogstarmusic/ |
| Projects, Vacuum Tubes & other stuff: |
| http://www.dogstar.dantimax.dk |
+--------------------------------------------+

Fred Nachbaur wrote:



OvrReactor wrote:

For the past year, Ive been making regulated linear power supplies
for my
own audio projects AND for sale to others. For most audio projects, a
regulated B+ is overkill, so Ive been installing a jumper across the
regulator section of my PC boards and making a few plain old low
tech, saggy B+
supplies, and they have worked out great. Now that Im happy with them,
Ive decided to gear up for production on these and add them to my power
supply product line.

[...]

Neat! Good additions to your line. Fine for preamps, etc. or
flea-power PA's.

Can your supplies feed the high frequency AC (the switching frequency, which
I assume is supersonic) at low voltage and high current to drive the
filament of
a directly heated triode? This would avoid hum from the filament supply and
avoid the downsides of a DC supply.

Neat! Good additions to your line. Fine for preamps, etc. or flea-power
PA's.

Are you contemplating any gutsier ones? (E.g. 350 v at 100 mA for things
like pp 6BQ5, 6V6, etc.)

Cheers,
Fred

Hi Fred,

There's a few more "projects" I need to finish before I move on to a large
power supply like that. I've been tinkering with a board with twin supplies,
6.3 V regulated at 1.4 A, and 250 V regulated at around 20 mA (with an option
to bypass the HV regulator), and possibly a similar version with a third output
of 48 V. They will be low profile, and will fit in a 1U chassis. I'm probably
at least 6 months away from that one. I also plan to do some beefier single
output supplies like a 24V one for powering Neve modules and another to power
up to four 12a*7 heaters at once. Gimme a year or so to make supplies for
power amplifiers.

I DO need development capital though. People need to buy the stuff I have now
so I can afford to make some NEW stuff.

Best regards,
Tom Mitchell
website - http://members.aol.com/ecc81

Can your supplies feed the high frequency AC (the switching frequency, which
I assume is supersonic) at low voltage and high current to drive the
filament of
a directly heated triode? This would avoid hum from the filament supply and
avoid the downsides of a DC supply.

It sounds like you're asking for a switching supply. Since I like tubes, I'm
obviously a Luddite, and all of my power supplies are linears I've avoided
switchers for two reasons, 1.) I don't trust them, and 2.) I haven't had the
time to climb the learning curve of switcher design.

Computer processor voltages are dropping WAY low, and they all need low voltage
high current regulated power, so I'm sure that some pointy headed pocket
protector type who reads this NG can chime in with a solution for your
application...

;-)

Best regards,
Tom Mitchell
website - http://members.aol.com/ecc81

OvrReactor wrote:

Can your supplies feed the high frequency AC (the switching frequency, which
I assume is supersonic) at low voltage and high current to drive the
filament of
a directly heated triode? This would avoid hum from the filament supply and
avoid the downsides of a DC supply.



It sounds like you're asking for a switching supply. Since I like tubes, I'm
obviously a Luddite, and all of my power supplies are linears I've avoided
switchers for two reasons, 1.) I don't trust them, and 2.) I haven't had the
time to climb the learning curve of switcher design.


I had a brain fart. Somehow I thought I saw "switching", but upon a re
reading of your post
it definately said "linear". Duhh....

"Fred Nachbaur" wrote in message
news:yv85b.132594$K44.100040@edtnps84...


OvrReactor wrote:
For the past year, I've been making regulated linear power supplies for
my
own audio projects AND for sale to others. For most audio projects, a
regulated B+ is overkill, so I've been installing a jumper across the
regulator section of my PC boards and making a few plain old low tech,
saggy B+
supplies, and they have worked out great. Now that I'm happy with them,
I've decided to gear up for production on these and add them to my power
supply product line.
[...]

Neat! Good additions to your line. Fine for preamps, etc. or flea-power
PA's.

Are you contemplating any gutsier ones? (E.g. 350 v at 100 mA for things
like pp 6BQ5, 6V6, etc.)


Hi Fred -
Last time I was at my fave swap, I was hopin' to find a HV supply (mainly so
I can cleanly modulate the SG's in my toob cooker/tracer), and, of course,
when you need one, no luck. 'till I spotted a "transistor power supply".
Looking inside, nothin' but toobs. Voltage? Nominal 0-100, regulated by a
pair of 5881's (i like them things in some fenders, yanked them & put 6l6's
in). Changed the power tranny, added a sep. regulator fil. tranny, and
changed the reg. circuit to give 0-400V. Now, where was the "transistor"
part? There's not a single chunk of silicon in the thing, never was...
Even the ref. voltages are gas toobs... Oh, check my other post for a few
brags & questions about a SEP 807 "vintage" guitah' amp (it's done...)
-dim
-dim
Cheers,
Fred
--
+--------------------------------------------+
| Music: http://www3.telus.net/dogstarmusic/ |
| Projects, Vacuum Tubes & other stuff: |
| http://www.dogstar.dantimax.dk |
+--------------------------------------------+