Re: [Elecraft] RANT front end protection
On 2/8/06 3:14 PM, Gil Stacy [EMAIL PROTECTED] wrote: I have seen advertised front end protectors recommended for use when utiilzing a separate antenna for receive. Does the K2's RANT option on the 160 board offer sufficient protection for use with a separate preamp and RX antenna or is it prudent to use a front end protector such as designed by KD9SV? Thanks, The K2 is the only current production HF transceiver that I know of that has the front-end saver built in. The RECEIVE ANTENNA RELAY, K2 on the K160RX board, disconnects the RX antenna during transmissions. If you're running a standalone station, no problem. In an SO2R or other multi-station contest environment (or if you have a big gun station next door), you will probably need to take additional protective measures. Your best bet is to get a copy of Managing Interstation Interference by W2VJN (George of INRAD fame). He does a great job of describing the problems and solutions. Gus Hansen, KB0YH ___ 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] RANT front end protection
On February 8, 2006 04:15 pm, Augie (Gus) Hansen wrote: The RECEIVE ANTENNA RELAY, K2 on the K160RX board, disconnects the RX antenna during transmissions. Gee, I hope not. I thought that the K2 was completely solid state T/R switching. No clacking relays. Darrell VA7TO K2 # 5093 -- Darrell Bellerive Amateur Radio Stations VA7TO and VE7CLA Grand Forks, British Columbia, Canada ___ 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] RANT front end protection
Latching relays are used for the 160M band pass filter and the RX antenna switch from the K160 RX manual K3YT ___ 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] RANT front end protection
sri that should say low pass K3YT ___ 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] RANT front end protection
Additionally, newer production K2s also include back-to-back diodes (1N4148) across the RX antenna input, actually across pins 4 6 of U12 on the RF board. These diodes do a great job of protecting the K2 from very strong nearby transmitters. I'd doubt that you might need too much more. When I was field testing this mod prior to its being accepted, I had the K2 connected to my 80/40/30 triple-wire inv-V which is situated 3' below my tribander, and I transmitted with a KW into the tribander and received on the K2 with no damage to the K2's front end, or to any other of the RF stages. 73, Tom N0SS At 06:15 PM 2/8/2006, Augie (Gus) Hansen wrote: On 2/8/06 3:14 PM, Gil Stacy [EMAIL PROTECTED] wrote: I have seen advertised front end protectors recommended for use when utiilzing a separate antenna for receive. Does the K2's RANT option on the 160 board offer sufficient protection for use with a separate preamp and RX antenna or is it prudent to use a front end protector such as designed by KD9SV? Thanks, The K2 is the only current production HF transceiver that I know of that has the front-end saver built in. The RECEIVE ANTENNA RELAY, K2 on the K160RX board, disconnects the RX antenna during transmissions. If you're running a standalone station, no problem. In an SO2R or other multi-station contest environment (or if you have a big gun station next door), you will probably need to take additional protective measures. Your best bet is to get a copy of Managing Interstation Interference by W2VJN (George of INRAD fame). He does a great job of describing the problems and solutions. Gus Hansen, KB0YH ___ 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] RANT front end protection
Gil, I doubt that a 'front-end protector' would be required on the K2 RANT input - the input path is through D3 and D4 in the T/R switch, and both are back biased with the 8T signal during transmit - so as long as the peak signal on the receive antenna is less than the bias voltage on the diodes (8 volts), the signal should not get through - OK, consider 2,67 volts for a safety factor of 3). If you feel that this is not good enough, you may want to install a pair of back to back diodes directly across the receive antenna jack. As for the protection of a separate receive preamp - I can give no response since I know nothing about your particular preamp and connections - again, a pair of back to back diodes (1N4148 or similar) across the preamp input should provide adequate protection if required - a couple of 1N4148 diodes is likely much less expensive than a commercial 'front-end protector', and I would guess that such a device is nothing more than a pair of diodes (of course, I am speaking from ignorance since I have not investigated any such devices). 73, Don W3FPR -Original Message- I have seen advertised front end protectors recommended for use when utiilzing a separate antenna for receive. Does the K2's RANT option on the 160 board offer sufficient protection for use with a separate preamp and RX antenna or is it prudent to use a front end protector such as designed by KD9SV? Thanks, Gil NN4CW K2 #3104 ___ 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
