Hi Tim, I have used these BN-73-202 for quite a while. This is the only one that was in such small pieces.
N2TK, Tony From: Tim Shoppa <[email protected]> Sent: Monday, October 5, 2020 8:42 AM To: [email protected] Cc: topBand List <[email protected]> Subject: Re: Topband: Receive ant - binocular cores Tony, I have abused BN-73-202 cores at the 100W level when I accidentally transmit into the receive antenna through the transformer. I have smoked the termination resistor but never damaged the transformer by transmitting into them. I have used single BN-73-202 cores at the several watt level continuously, in step-up/step-down voltage inverter applications. None of the above means that the core would survive a lightning strike. The ferrite material is mechanically fragile. When (for example) PCB mounting in outdoor conditions you have to take into account the lead stress from temperature changes etc. I think the two-hole BN form is way more mechanically robust than the skinny rings but I have broken both kinds due to mounting them "too tightly down" to a PCB. Tim N3QE On Mon, Oct 5, 2020 at 7:19 AM tony.kaz--- via Topband <[email protected] <mailto:[email protected]> > wrote: I use BN-73-202 cores for my receive antennas - Pennants, BOGs. Finally getting time to check out my receive antennas. One BOG was very low. The BOG transformer was broken. I mean it was totally destroyed. The largest piece was 1/8" long. The primary and secondary wires, #30 were intact and neither open or shorted. The wire looked pristine. Any ideas what could do that to a ferrite core? Any reason I should change anything other than just wire another transformer? N2TK, Tony _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
