RE: [Repeater-Builder] Celwave CC460-A circulator
The simplified instructions for tuning an isolator are: 1. Tune input (tx port) for maximum return loss with antenna port terminated in 50 ohms and reject load connected to reject port 2. Tune output (antenna port) for minimum insertion loss, sweeping from tx port to antenna port, again with reject load connected to reject port 3. Tune reject port for maximum isolation (i.e. best match into load), sweeping from antenna port to transmitter port, adjusting for minimum amplitude 4. Repeat. If you're trying to use it far from its design frequency, you may not get it to meet spec, or you may find that the return loss maximum in step #1 doesn't align well with insertion loss minimum in step 2, or other similar performance problems. The Celwaves usually tune over a fairly broad range, so I think you have a good chance of having it work right, assuming you have the right test equipment to tune it. --- Jeff WN3A > -Original Message- > From: Repeater-Builder@yahoogroups.com > [mailto:repeater-buil...@yahoogroups.com] On Behalf Of cruizzer77 > Sent: Wednesday, August 18, 2010 3:19 PM > To: Repeater-Builder@yahoogroups.com > Subject: [Repeater-Builder] Celwave CC460-A circulator > > > > Does anyone have a datasheet or tuning instructions for this > kind of circulator? It's a single stage with 3 adjustment > screws and right now the sticker says it's on 420 MHz and I > would like to know how I get a working range from 430 to 440 > MHz. If somebody can explain without the doc this is fine as well. > > 73 > Martin > > > > >
Re: [Repeater-Builder] Celwave CC460-A circulator
Hello Martin Have you contacted Celwave to see if the have tuning specs usually for these. I am not sure if you will get it up to 440 or not. I was told that they are pretty narrowband, but I might be wrong. YMMV Butch, KE7FEL/r On Wed, Aug 18, 2010 at 1:18 PM, cruizzer77 wrote: > > > Does anyone have a datasheet or tuning instructions for this kind of > circulator? It's a single stage with 3 adjustment screws and right now the > sticker says it's on 420 MHz and I would like to know how I get a working > range from 430 to 440 MHz. If somebody can explain without the doc this is > fine as well. > > 73 > Martin > > >
Re: [Repeater-Builder] Celwave CC460-A circulator
Hi, Harold Kinley wrote an excellent article in MRT magazine a few years ago on aligning circulators. Maybe they still have re-prints. I have old contact details for Harold Kinley taken from MRT magazine. See below. You should also buy his *Standard Radio Communications Manual, with Instrumentation and Testing Techniques. * Contributing editor Kinley, *MRT's* technical consultant and a certified electronics technician, is regional communications manager, South Carolina Forestry Commission, Spartanburg, SC. He is the author of *Standard Radio Communications Manual, with Instrumentation and Testing Techniques,* which is available for direct purchase. Write to 204 Tanglewylde Drive, Spartanburg, SC 29301. His email address is halkin...@charter.net. On Wed, Aug 18, 2010 at 3:18 PM, cruizzer77 wrote: > > > Does anyone have a datasheet or tuning instructions for this kind of > circulator? It's a single stage with 3 adjustment screws and right now the > sticker says it's on 420 MHz and I would like to know how I get a working > range from 430 to 440 MHz. If somebody can explain without the doc this is > fine as well. > > 73 > Martin > > >
