-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
Quick and Dirty Class "AB" mod for KL300p
- Thread starter eagle1911
- Start date
Does anyone know of a way to view the pics on this thread? Looks like photo bucket has blurred them.
Yup, sure are blurred. A few of the posters are still very active here so hopefully they will post up
Yeah, I hope so. I can understand the written instructions, but the pictures would be nice. I have a 1x4 class C amplifier with Toshibas. Trying to decide if I should sell it, or remove the driver and try to properly bias it, so I can use it for...something. Lol.
I did a board about the sametime as the OP posted this thread but can't find the notes I had. It work on a X-Force 2 pill I had very well.
Personally, drop the 1x portion of the amp.
Personally, drop the 1x portion of the amp.
See attached file;
Good to see some other working on adding Bias. I've been slowly collecting parts to redo the bias in a Palomar 900HD (4x2879). As such, the amp already had the Tip31c and 7805 Regulator circuit for bias. I began modding it to run at 28v with 4x MRF422's (I have HG's). My idea was replacing the 7805 and PCB trim-pot with a lower V regulator and using a panel-mounted 10T precision pot to adjust as needed. A calibrated 1v panel meter would fit nicely to aid in monitoring/setting bias v as needed. The variable bias idea I read long ago on R. Measures (Silent Key) SB220 website.
It was the ifw reference to G3SEK that got my attention. I built Ian's Tetrode boards where bias is 'steadied' by standing Screen current to help stabilize Screen voltage.
Anywho, we both got to the same place from opposite directions LOL.
It was the ifw reference to G3SEK that got my attention. I built Ian's Tetrode boards where bias is 'steadied' by standing Screen current to help stabilize Screen voltage.
Anywho, we both got to the same place from opposite directions LOL.
I'm having problem with regulator heat on paper when dropout V is factored in with 28v source.
Need to divide it down a bit...standing current. 4 MRF422's need 400mA for AB which is a lot of heat. Must include small fan. 1v meter from PRC is taking forever, Orange Connex is terribly slow.
Need to divide it down a bit...standing current. 4 MRF422's need 400mA for AB which is a lot of heat. Must include small fan. 1v meter from PRC is taking forever, Orange Connex is terribly slow.
Use buck converter, or high wattage resistor inline, before regulator. All the heat will be on resistor.