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That's the term we have been using for ages. It means that one diode is placed with the cathode connected to one side of the circuit and the other connected the other way round so that they clip both

I have been trying to reduce the 2nd and 3rd harmonics leaving the BITX40v3 for days and I just added the 100pf capacitor across L7 LPF coil and I will say it has solved all of my problems with higher

Looks like PD8W was written to drive the BFO with CLK0 from the Si5351 instead of using the Bitx40 analog BFO. Though that is only activated if this line turns it on: ? ??#ifdef IF_Offset My guess

Jerry, Ok, thanks for some suggestions. I have a good frequency counter which I use to monitor the actual vfo clock , also have hf rigsand websdr to listen with. jgaffke@...>

I don't know anything about this PD8W code. However, somewhere in the PD8W code it says: ? ??volatile uint32_t USB = 1200150000ULL; That code you borrowed from Allard is treating the variable USB

Jerry, Thanks for your reply.? I have been trying various combinations. The one I have decided to work on is from?Allard PE1NWL. He provided the suggested code below: if (USB) // if we are in UPPER

1n4148's seem to work fine. 1n914's likely do as well, the Vishay datasheets look about the same. Could be Vishay ships the exact same part. The 1n914 is older, other manufacturers might spec a lower

Yes the diodes are in "Anti-Parallel" not "Anti-Series". Anti-Parallel = parallel but cathodes on opposing sides; I had been wondering if we were talking PIN diodes or what, 4148s I "might" have 2-3

Just looked at Farhan's diagram. K1-12 to K2-14 line is connected through on Rx, and isolated on Tx.

Back to back? I think not! That gives avalanche/breakdown voltage, and that can be up to kV depending on device. Try Head to tail - and across the input. +/-0.6V max, turn-on (forward-bias) voltage of

Good luck rd232d@...> wrote:

There is a product called "Desitin", it is used on infants to treat diaper rash. It is pretty much just zinc oxide (get the plain kind without any extra stuff in it), it makes for pretty good heatsink

Al & Lawrence: Thank you. I am slowly gathering the pieces :) ? Mark KF7YTQ

I used compound when I mounted it to the 5"x8" heat sink inside it's case. Vince. -- Michigan VHF Corp. http://www.nobucks.net/ http://www.CDupe.com/

Best to use heatsink compound It helps transfer heat to the heat sink and any imperfections between the heatsink and the transistor etc wrote:

The military and consumer electronics that I worked on all used heat sink compound to increase the efficiency of heat to the heat sink. It sure wouldn’t hurt and might help if used with the

Heat sink paste is used to fill in any imperfections on the surface of the IRF tab and the heatsink. You don't have to use it, but it might transfer the heat from the IRF tab more evenly allowing for

When I swapped out the IRF510 in my first Bitx I noticed that they didn't use and heat sink paste so I'm guessing that the new one is the same way. ?Has anyone added heat sink paste or is it really

Yes, 25v. Mounted on a heat sink approximately 15 in^3.

Are you running the final at something in excess of 12v to get higher power? 24v is quite a lot if the antenna is shorted. And 24v requires a larger heatsink. A shorted antenna means excess current