Well only one really. The recent Parasitic choke threads on here, as opposed to older threads, were interesting and reasonably concise. I appreciate well enough that there are likely many unknowns th
Ameritron uses a MOX resistor with capacitors to cancel out the XL. Works fine. Carl KM1H _______________________________________________ Amps mailing list Amps@contesting.com http://lists.contesting
Hi all, I have a Heathkit HL2200 that was built by NC8V (SK). (Uses a pair 3-500Z's) I bought it from him while he was still alive and he gave me a photocopy of modifications to help the stability. O
Thats fine if you dont mind losing up to 100W on 10M from a voodoo suppressor. If the original didnt work it means the resistors were fried and out of tolerance. Take a look at any real amp from the
Oh dear, I really didn't want to drag this old horse from its resting place to start another flogging match. Apologies to Greg though as my original message was rather cryptic in its reference to thi
What is preferred about carbon comp? Given the heat and the need for long term stability in value they're the least suitable component you could choose. Some years ago I measured some different supp
None of these apply! All these resistors are meant to do is lower the Q of the suppressor inductance and dissipate the harmonic energy involved. Their stability is of no concern, since the circuit is
The role of a suppressor is to stop a parasitic from starting in the first place. If it absorbs power it is not designed properly or is simply a brute force method using a sufficiently high wattage r
With such a low Q involved the effect is miniscule and not noticed, it is mostly cancelled out by its own R. Of course the main L should be very low loss and the complete suppressor should not absorb
Maybe we have different ways of visualising what the suppressor is doing and how it does it. With regard to stability, I wasn't meaning the few % of tolerance or temperature drift, but the factor of
ORIGINAL MESSAGE: REPLY: Not absorb "any" of the desired HF power? That is impossible and Carl should know better than to make such a statement. The trick is to keep the power loss on the highest HF
ORIGINAL MESSAGE: REPLY: Least amount of internal parasitic inductance. The current path in a carbon comp is straight through as opposed to some film type resistors which have a spiral cut resistive
I chose my words for the sake of brevity and the ideal situation. Do you have a problem with that or are you just up to the usual nit picking so you can see your words on the screen? You remind me of
ORIGINAL MESSAGE: REPLY: A lot of members of this reflector are new to amp building and need good, reliable information. Misleading them as you did with your comment does not help. Electronics is har
Getting back to the nichrome, or resistive material for the coil, I'd think the only thing it'd do would be to lower the Q with an increase in temperature. So in the case of 10 meters, if it started
The nichrome is taking the place of a low loss inductor, often made from wide silver plated strap in commercial grade and military amps, and tinned with a resistive element that has some inductance.
Good, reliable information is always available from the archives at a click of the mouse going back to the 90's. Thats the information a newcomer should really search if he is serious about building
This was somewhat germane to my original question. Really more about how much preferred a purely carbon resistor would be to one of the more modern equivalents. Having done a little digging, RADCOM J
ORIGINAL MESSAGE: REPLY: That would be a pretty blank picture. My amps do not need or have VHF parasitic suppressors. In my early days I put them in because everyone did, but I came to realize that t
Here's the one from 30/8/06, which details measurements on some suppressors, plus a brief explanation of how I think suppressors should be analysed. http://lists.contesting.com/archives//html/Amps/20