PDA

View Full Version : LRL using Valves


Delbert grady
10-23-2007, 11:35 PM
For an old rocker like me, there is belief that valves ( vacuum tubes ) work better in some guitar amps. This led me to thinking that some LRL’s may work better if they could use a few valves and perhaps some Germanium transistors in their circuits. May get better range and pinpointing using valves. Need to carry a 60 volt battery though.
LRL using valves may be immune to Dicky spy problems.

Geo
10-24-2007, 05:31 AM
Five batteries 12v/2,4ah are not so big problem. The problem is who knows to make a good LRL (or how it work so to construct one)
Regards:)

Max
10-24-2007, 06:53 AM
For an old rocker like me, there is belief that valves ( vacuum tubes ) work better in some guitar amps. This led me to thinking that some LRL’s may work better if they could use a few valves and perhaps some Germanium transistors in their circuits. May get better range and pinpointing using valves. Need to carry a 60 volt battery though.
LRL using valves may be immune to Dicky spy problems.

Hi,
about tubes: they are more stable than transistors or fets or anything silicon or germanium based semiconductor.

It's physics. Semiconductors have minority carriers that quantity is related to structural parameters of doped crystal... and temperature (or other things like that) ... and instead tubes haven't minority carriers.

Tubes have vacuum or controlled atmosphere inside (some inert gas)... then except cold catode ones... they have all hot catode... and really often separate heater (tungsten filament).

They have also special treatment on leads... etc that make their params should remain almost the same for a very long time during operating life.

That means tubes e.g. oscillators are much more stable on temperature than a transitor or fet same kind of osc. Stability about both frequency and e.g. amplitude I mean... after warm-up phase.

Problem is not having 60 or more volts... you can generate with a flyback or something from e.g. 12V... it's all easy today about supply.

Kind regards,
Max

Delbert grady
10-24-2007, 01:59 PM
What about using valves from old East European cars. I had a Skoda that had 16 valves. There were 8 in the engine and 8 in the radio.

roberts
10-24-2007, 03:03 PM
...or can i dismantle my Messa Boogie and use 6L6gc ?
750v anode voltage would do the job just fine?!:D:D:D

Max
10-24-2007, 03:12 PM
What about using valves from old East European cars. I had a Skoda that had 16 valves. There were 8 in the engine and 8 in the radio.

Hi,
could be an idea ! :lol:

But you have also to consider that if you need some tubes today you must buy from ukraine or russia or bulgaria... anyway you couldn't find them on the western market... cause western guys don't like to play with tubes anymore... apart youtube stuff. :rolleyes:

Some brands from eastern countries are maybe not so funky for a western mind... but they are often even better than western made old stuff ... think at some DIY audio projects today that need ultra low noise tube amplifiers... could be impossible making that stuff using just recovered of NOS parts.

That's why I like these countries way of thinking about business... they don't leave a technology completely adbandoned but continue producing stuff that I can use...and even cheap and good! And that's all important to me.

Well... I don't know if one could made an LRL using tubes... but if you need tubes, for one reason or another, THERE ARE ! :)

Now think you have a masterpiece to repair... and no tubes... and have to look around and try to find one in London or NY... :lol: one could become crazy in no time watching at flea markets for them...:rolleyes: without finding even one. :shocked:

Kind regards,
Max

roberts
10-24-2007, 03:13 PM
:razz::lol:I mixed up things, actually it is 500v plate voltage. I ment on KT88 when mentione 750v...:D

roberts
10-24-2007, 03:17 PM
Speaking of tubes...