[Elecraft] Testing BL1 mini module
I finished assembling a BL1 BALUN Module and decided to test it with my 259 Antenna Analyzer. The testing procedure calls for you to connect a pair of 100 ohm resistors in series between the two 200 ohm terminals, then test the SWR with a jumper connected to the input shield and to three different locations on the resistors. The instructions state that the SWR should be low when the jumper is connected between the input shield and the junction between the two resistors. Then it should show poor SWR when the jumper is connected between the input shield and either one of the BALUN output terminals. My tests showed no difference between any of the three connections. I have double and triple checked my soldering connections on the BL1. It is not a complicated module to assemble. Has anyone else tested the BL1 with a 259? Is the BALUN safe to use or should I just stay away from testing equipment without adult supervision? 73, KI4DGH Chuck Gehring ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Testing BL1 mini module
Chuck, I don't have one, but I have the manual and have studied it and the balun. I would test it by placing the 200 ohms across the antenna connections, and connect the 259 to the 50 ohm connection. It is a voltage balun, but should have a decent SWR from 3.5 to 29 MHZ when so connected. If it still doesn't read 1.2:1 or less, check your connections of all the wires. Chas, W1CG At 01:38 PM 11/26/2004, Chuck Gehring wrote: I finished assembling a BL1 BALUN Module and decided to test it with my 259 Antenna Analyzer. The testing procedure calls for you to connect a pair of 100 ohm resistors in series between the two 200 ohm terminals, then test the SWR with a jumper connected to the input shield and to three different locations on the resistors. The instructions state that the SWR should be low when the jumper is connected between the input shield and the junction between the two resistors. Then it should show poor SWR when the jumper is connected between the input shield and either one of the BALUN output terminals. My tests showed no difference between any of the three connections. I have double and triple checked my soldering connections on the BL1. It is not a complicated module to assemble. Has anyone else tested the BL1 with a 259? Is the BALUN safe to use or should I just stay away from testing equipment without adult supervision? 73, KI4DGH Chuck Gehring ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] Testing BL1 mini module
Hi Chuck, I designed the BL1 for Elecraft and I am curious as to where you got the testing procedure that you describe. I don't find it on the posted manual and it is certainly not what I wrote. That said, the behavior that you observe is exactly what I would expect the BL1 to do. Shorting one side to the ground side of the coax will have little effect on SWR except at the lowest frequencies where you are removing part of the transformer inductance. In normal operation, i.e. no short, the two halves of the transformer are connected in series which improves the low frequency response. Testing the BL1 with a 200 ohm resistor across the output terminals and looking at the SWR at the coax connector is entirely adequate. No shorts, opens etc. are needed. 73, Bob, N6CM - Original Message - From: "Chuck Gehring" <[EMAIL PROTECTED]> To: Sent: Friday, November 26, 2004 10:38 AM Subject: [Elecraft] Testing BL1 mini module I finished assembling a BL1 BALUN Module and decided to test it with my 259 Antenna Analyzer. The testing procedure calls for you to connect a pair of 100 ohm resistors in series between the two 200 ohm terminals, then test the SWR with a jumper connected to the input shield and to three different locations on the resistors. The instructions state that the SWR should be low when the jumper is connected between the input shield and the junction between the two resistors. Then it should show poor SWR when the jumper is connected between the input shield and either one of the BALUN output terminals. My tests showed no difference between any of the three connections. I have double and triple checked my soldering connections on the BL1. It is not a complicated module to assemble. Has anyone else tested the BL1 with a 259? Is the BALUN safe to use or should I just stay away from testing equipment without adult supervision? 73, KI4DGH Chuck Gehring ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
