Hi Grant. Tnx for the info. Putting up a DHDL like at H40TT is on my list. I want to install another BOG first for a comparison to my 3-el W1FV and two dual feed Pennants. I miss my 625' beverage I had in Joisey. I don't have the room here. N2tK, Tony
-----Original Message----- From: Grant Saviers <[email protected]> Sent: Sunday, December 8, 2019 11:56 AM To: [email protected]; [email protected] Subject: Re: Topband: 12V through coax For my relay reversible DHDL's used on 160 & 80m, I'm using 0.1uf 500v DC blocking capacitors, particularly the Kemet X7R MLCC SMD ones. digikey 399-6747-1-nd There are enough parts for reversibility that I designed a small PCB with ExpressPCB so SMD parts made sense. The RFC inductor choice depends on the current draw, for my design, all in was 92ma so a ferrite core design with a saturation current (10% reduction in L) of 120ma was ok at 450uH and an SRF of 4.5MHz. From Wurth, SMD again. digikey 732-10766-1-ND Automotive grade thick film 1/2 and 1w SMD resistors have very high surge ratings so are what I used for terminators. If you have some old A-B carbon ones in your stash, they are a good choice. These parts worked well at H40TT on two DHDLs and we had some T-storms nearby without damage. Grant KZ1W On 12/7/2019 20:59, tony.kaz--- via Topband wrote: > I am making up new boxes for my Pennants. I will be switching > directions with a relay in the box besides the terminating resistor and the > choke. > My question is what are the correct values of the components for > feeding the 12V? I will be using this only on 160 and 80M. > For the coupling cap between the rig and antenna I have seen values > from .01-.1uf. For the choke I have seen values from 100 uhy - 4.7 mh. > On the 12V feed side I have seen values from .01 - .1 ufd. > Is there a rule of thumb for the range of correct values for 80 and 160M? > Thanks > N2TK, Tony > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
