RE: [Repeater-Builder] Micor oscillator mod question
No one has answered his original question, that is: What benefit does he get by wiring the exciter to be ON all the time? I think he's discovered one of the non-benefits and is trying to figure out if the leakage he's experiencing is worth the effort. Even a well-shielded and filtered repeater station will leak something. Personally, I think I'd only keep just the oscillator running all the time, not the entire exciter. The only reason I can think of doing this is if the oscillator is slow to come up to frequency when the station is keyed. I would expect it to take only milliseconds for stability to occur, so there really shouldn't be any noticeable benefit. The exciter is putting out a whole lot more RF power than the oscillator. Perhaps this is really what he's done, or should do. Bob M. == --- Eric Lemmon [EMAIL PROTECTED] wrote: Jordan, Assuming your Micor station has a unified chassis, was it always a repeater, or was it converted to repeater use from a base station? Repeater stations have a great deal of extra filtering in the interconnect boards that connect the RX and TX shelves to the backplane. The repeater chassis also is equipped with extra shield plates that cover the RX and TX shelves, which plates should be secured with all screws in place. The purpose of the extra filtering and shielding is to prevent (or greatly attenuate) any direct radiation from the exciter oscillator or the RX injection oscillator. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of twoway_tech Sent: Monday, May 28, 2007 9:15 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor oscillator mod question I just modified my micor UHF for the exciter to be on all of the time. I am not for sure that I really like this mod. The oscillator signal seems to carry pretty far. Can someone tell me exactly what is gained by wiring the exciter to be on all of the time. Is it just for faster transmit response time? Thanks I'm sure there will be more questions to come! Jordan, K9NZF Looking for earth-friendly autos? Browse Top Cars by Green Rating at Yahoo! Autos' Green Center. http://autos.yahoo.com/green_center/
Re: [Repeater-Builder] Micor oscillator mod question
The exciter should NEVER be run full time. A Micor exciter will develop 400 milliwatts, that's 0.4 watts and that much loose RF running around loose in the station is asking for trouble. Running the channel element full time is often done, but not a good idea, it's much better to switch the channel element on as needed. The use of the antenna switch transistor on the station control module as shown on repeater builder is an excellant idea. Milt N3LTQ - Original Message - From: Bob M. [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, May 30, 2007 6:41 AM Subject: RE: [Repeater-Builder] Micor oscillator mod question No one has answered his original question, that is: What benefit does he get by wiring the exciter to be ON all the time? I think he's discovered one of the non-benefits and is trying to figure out if the leakage he's experiencing is worth the effort. Even a well-shielded and filtered repeater station will leak something. Personally, I think I'd only keep just the oscillator running all the time, not the entire exciter. The only reason I can think of doing this is if the oscillator is slow to come up to frequency when the station is keyed. I would expect it to take only milliseconds for stability to occur, so there really shouldn't be any noticeable benefit. The exciter is putting out a whole lot more RF power than the oscillator. Perhaps this is really what he's done, or should do. Bob M. == --- Eric Lemmon [EMAIL PROTECTED] wrote: Jordan, Assuming your Micor station has a unified chassis, was it always a repeater, or was it converted to repeater use from a base station? Repeater stations have a great deal of extra filtering in the interconnect boards that connect the RX and TX shelves to the backplane. The repeater chassis also is equipped with extra shield plates that cover the RX and TX shelves, which plates should be secured with all screws in place. The purpose of the extra filtering and shielding is to prevent (or greatly attenuate) any direct radiation from the exciter oscillator or the RX injection oscillator. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of twoway_tech Sent: Monday, May 28, 2007 9:15 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor oscillator mod question I just modified my micor UHF for the exciter to be on all of the time. I am not for sure that I really like this mod. The oscillator signal seems to carry pretty far. Can someone tell me exactly what is gained by wiring the exciter to be on all of the time. Is it just for faster transmit response time? Thanks I'm sure there will be more questions to come! Jordan, K9NZF Looking for earth-friendly autos? Browse Top Cars by Green Rating at Yahoo! Autos' Green Center. http://autos.yahoo.com/green_center/ Yahoo! Groups Links
Re: [Repeater-Builder] Micor oscillator mod question
twoway_tech wrote: I just modified my micor UHF for the exciter to be on all of the time. I am not for sure that I really like this mod. The oscillator signal seems to carry pretty far. Can someone tell me exactly what is gained by wiring the exciter to be on all of the time. Is it just for faster transmit response time? Thanks I'm sure there will be more questions to come! Station? We use the (unused) antenna switch logic (on the SCM) to control the channel element ground. Works great, less filling... Kevin
RE: [Repeater-Builder] Micor oscillator mod question
Jordan, Assuming your Micor station has a unified chassis, was it always a repeater, or was it converted to repeater use from a base station? Repeater stations have a great deal of extra filtering in the interconnect boards that connect the RX and TX shelves to the backplane. The repeater chassis also is equipped with extra shield plates that cover the RX and TX shelves, which plates should be secured with all screws in place. The purpose of the extra filtering and shielding is to prevent (or greatly attenuate) any direct radiation from the exciter oscillator or the RX injection oscillator. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of twoway_tech Sent: Monday, May 28, 2007 9:15 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor oscillator mod question I just modified my micor UHF for the exciter to be on all of the time. I am not for sure that I really like this mod. The oscillator signal seems to carry pretty far. Can someone tell me exactly what is gained by wiring the exciter to be on all of the time. Is it just for faster transmit response time? Thanks I'm sure there will be more questions to come! Jordan, K9NZF
