Author Topic: Hs treble booster parts list and schematic  (Read 470 times)

Andrevkammen

Hs treble booster parts list and schematic
« on: June 17, 2022, 04:06:01 AM »
Hi

Thanks for adding me.
Does anyone have a schematic and parts list for a hs treble booster?

iainpunk

Re: Hs treble booster parts list and schematic
« Reply #1 on: June 17, 2022, 08:01:48 AM »
welcome to the forum,

its basically a clone of a clone of the Range Master. i suggest building some sort of rangemaster clone, but with a socket for the input capacitor and experiment with that value until you like what you hear.

cheers
friendly reminder: all holes are positive and have negative weight, despite not being there.

cheers

antonis

Re: Hs treble booster parts list and schematic
« Reply #2 on: June 17, 2022, 08:33:04 AM »
Hi & Welcome.. :icon_wink:



edit: 18.5 cap/frequency product only stands for this very particular input impedance (8k6)  :icon_wink:
« Last Edit: June 17, 2022, 09:03:50 AM by antonis »
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

pacealot

Re: Hs treble booster parts list and schematic
« Reply #3 on: June 17, 2022, 01:27:06 PM »
I believe there's some, er, spirited disagreement, shall we say, about what the "correct" Hornby-Skewes schematic is, including debate around whether the tranny should be silicon or germanium and/or both at different times (but I think consensus is that Aron's redrawn schemo that antonis posted is wrong about the JFET; allegedly the correct part number is 2N4061, a PNP silicon BJT, which was misread as 2N4861, an N-channel JFET). Additionally the lack of input/output caps on Aron's schemo is also an error (I assume it was antonis who drew in an input cap there, and fair play for that). So I suppose caveat emptor or buyer be weird, as one will. Me, I like a good treble booster just fine, but I'm not ready to bring this one home to meet the parents just yet...
« Last Edit: June 17, 2022, 01:40:35 PM by pacealot »
"Stupidity has a certain charm; ignorance does not." Frank Zappa

"I hate guitar players. Whatever." Scott Thunes

pacealot

Re: Hs treble booster parts list and schematic
« Reply #4 on: June 17, 2022, 01:47:10 PM »
(deleted due to posting an incorrect schematic)
« Last Edit: June 18, 2022, 08:57:37 PM by pacealot »
"Stupidity has a certain charm; ignorance does not." Frank Zappa

"I hate guitar players. Whatever." Scott Thunes

pacealot

Re: Hs treble booster parts list and schematic
« Reply #5 on: June 17, 2022, 01:59:47 PM »
(deleted due to being needlessly ignorant)
« Last Edit: June 18, 2022, 08:57:11 PM by pacealot »
"Stupidity has a certain charm; ignorance does not." Frank Zappa

"I hate guitar players. Whatever." Scott Thunes

antonis

Re: Hs treble booster parts list and schematic
« Reply #6 on: June 17, 2022, 03:04:29 PM »
I think consensus is that Aron's redrawn schemo that antonis posted is wrong about the JFET; allegedly the correct part number is 2N4061, a PNP silicon BJT, which was misread as 2N4861, an N-channel JFET). Additionally the lack of input/output caps on Aron's schemo is also an error

To be honest, low value bias resistors made me think the same.. :icon_wink:

(I assume it was antonis who drew in an input cap there, and fair play for that)

Any dark blue draw/text indeed is by Antonis.. :icon_wink:.

P.S.
IMHO, any treble booster can equivalently be considered as bass attenuator..
« Last Edit: June 17, 2022, 03:54:28 PM by antonis »
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

Electric Warrior

Re: Hs treble booster parts list and schematic
« Reply #7 on: June 18, 2022, 03:51:26 AM »
Here's an alternative schematic from elsewhen:



That's wrong. It should be 0.001F on the output, 0.022F on the input.

These should be correct:



antonis

Re: Hs treble booster parts list and schematic
« Reply #8 on: June 18, 2022, 06:54:36 AM »
I'm not sure what we're talking about but, in case of BJT device (either Si or Ge), in & out caps can readily be estimated by respective impedances, which are about 7k5 for input (hFE dependent) and 3k7 for output..

22nF cap for input results into 963 Hz corner frequency and 1n for output results into 43kHz..!! :icon_eek:
(the former might be Ok but the later calls for a -21dB attenuated(*) signal in the region of 5kHz, -27dB at 2k5Hz and so on..)

(*) compared to theoretical Collector output..
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

Electric Warrior

Re: Hs treble booster parts list and schematic
« Reply #9 on: June 20, 2022, 03:48:51 PM »
They were very consistent with that output cap  ;D
And it works alright that way. Not the greatest sounding booster, but not bad either.. I haven't built the germanium version yet, though..