[Tomo]

Hey!

That is awesome! I think I like your idea about planer resistors as I have never used them. I know it existed, but ... well I had my Dales which shouldn't go waste.

Do you know how they fair with the heat dissipation? I wonder if I need to bolt the thing.

Another thing, you can use series of LEDs to set the MOSFET Gate voltage. Voltage-divider is getting olde, but I would hate to use precious v-regulators.

Ciao,

T

 

[setmenu]

Quote:

Originally Posted by Tomo Hey! That is awesome! I think I like your idea about planer resistors as I have never used them. I know it existed, but ... well I had my Dales which shouldn't go waste. Do you know how they fair with the heat dissipation? I wonder if I need to bolt the thing. Another thing, you can use series of LEDs to set the MOSFET Gate voltage. Voltage-divider is getting olde, but I would hate to use precious v-regulators. Ciao, T

Thanks.
My circuit runs from a 12v 1.5A regulated transformer into a post regulator
taking it to 10v.
Quiescent current is around 200ma per channel.
The resistors are paralleled and don't' run particularly hot.
The Mossie heatsinks run hot but it is possible to hold a finger on them for
some time.
I have not run the circuit in high ambient temperature as yet.
I don't expect a problem as the power dissipation is not that big.
The circuit was designed specifically for my E4 phones so large voltage swings
are not an issue, my cdp puts out around the usual 2v out., plenty for 97%
of recordings.[including insertion losses of the filter network]
Strings of leds for setting the operating point would be pretty but I just
threw this together with bits I had laying about.
The mossies are irf610 devices.

.

 

[nikongod]

in a related question (sort of) what is the trim-pot for in the "jfet-mosfet" unity gain amp by richard murdley?

i read and re-read the description, but could not find this info.

link to headwize project description

thanks
nikongod

 

[doobooloo]

Quote:

Originally Posted by Tomo I wasn't planning on using this particular chasis (which is COOL)

That chassis IS very cool. What is it?

 

[Tomo]

Hi,

The trim pot in JFET-MOSFET combination done by RJM is for gate bias. It is similar to the gate bias for the original Szekeres amp. (Kinda drawn differently) Personally, I don't WANT voltage gain and I don't WANT a large voltage swing either. So I didn't use it on my new amp. (I suppose you just gotta sit down and play with schematics till you get it ... that is if you care. "I" do, but I won't force you.)

My chasis is probably from Hummond. You just look around at web stores. I know. 7.5cm X 8.3cm X 14cm ... (SI (mks/cgs) units are GLOBAL STANDARD, thank you very much.) It is pretty bad that you won't find a walk-in store in Philly.

Ya'l who know cool web-store based in US pitch in Plz!!

T

P.S. But I do now an awesome musician store midway between Bryn Mawr and Haverford. Darn R4 trains are never on time! Hey I couldn't buy a car when I was a highschooler, OK?

P.P.S. I still got no car!!! No parking space. Besides people drive on LEFT SIDE here!!! How rude!