KK7B Multimode Phasing Transmitter
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| Steampunk Incognito ~ Gathering Data & Science
(By any chance could this be a Special Assistant to the emperor (undersized e) Whiz Kid Panel Member only in disguise so he doesn't have to explain to Wall Street about their misadventures in buying PPE.)
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A PSA regarding Covid19. Summer is coming, thus we must never let our guard down and protect ourselves at all times. Social Distancing works! So does the use of masks and gloves such as ..
Easy to spot --- this is a YL as the foot covering and the flip flops are color coordinated. Another piece of evidence --- small feet. We all need a laugh in our day -- during this pandemic never lose your sense of humor!
[Yes, someone will point out the waste of precious PPE; but the emperor (with an undersized e) told a nurse yesterday there was not a PPE problem. Guess his "special adviser" told the "emp" that the whiz kids fixed all that!]
An 8 P0le Network from QuadNet ~ Tonne Software. A Free Download. Although have been advised this may have problems in the way you have to power the op-amps and the possibility of noise. I have also been made aware of an alternative to fix the power feed issue. Stay tuned.
With 8 poles, QuadNet says this is >60 dB opposite Sideband Suppression. BUT -- that >60dB can only be achieved with extremely close tolerance parts. There are analytical tools in the Tonne software that enable that evaluation. The >60 dB requires 0.1% or better resistors and if you use 1% resistors that drops to the 45 to 50 dB range. Using 10% is not worth the effort! One approach is to use a combination of close tolerance resistors along with precision trim pots (like W6JL) to put the network dead on. With 10 poles --that is 10 trim pots.
10 % Tolerance Resistors about 25 dB of Suppression.
1% Tolerance Resistor about 45 to 50dB of Suppression
0.1% Tolerance Resistors about 60 dB of Suppression
Once again this like most things in homebrew --this is not plug and play It is test, measure, re-test, tweak and then start breathing again. So if you simply go into the junk box and find a 10K 10% resistor and plug that in the 11K location on the schematic-- it ain't gonna work very well! But if it does --stop and go play the lottery as you are indeed full of luck!
With 8 poles, QuadNet says this is >60 dB opposite Sideband Suppression. BUT -- that >60dB can only be achieved with extremely close tolerance parts. There are analytical tools in the Tonne software that enable that evaluation. The >60 dB requires 0.1% or better resistors and if you use 1% resistors that drops to the 45 to 50 dB range. Using 10% is not worth the effort! One approach is to use a combination of close tolerance resistors along with precision trim pots (like W6JL) to put the network dead on. With 10 poles --that is 10 trim pots.
Once again this like most things in homebrew --this is not plug and play It is test, measure, re-test, tweak and then start breathing again. So if you simply go into the junk box and find a 10K 10% resistor and plug that in the 11K location on the schematic-- it ain't gonna work very well! But if it does --stop and go play the lottery as you are indeed full of luck!
The KK7B T2 Schematic
