Re: [Repeater-Builder] Crystals Motorola etc
Ralph, Before you make a decision on your supplier, please read the following article: www.repeater-builder.com/tech-info/temperature-compensation.html Unless you have a testing laboratory Another respectable option: do the following: http://www.repeater-builder.com/projects/no6b-crystal-heater.html Then, your result will be even better where temp stability is concerned. *If one of the elements are FM for transmit, then I'd send them to the crystal house. Kevin Custer
Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
I downloaded the manual on the CAT-200 and looked The CAT-200B has the ability to do de-emphasis, but, it's not as simple as flipping a dip switch; you must install a capacitor for adding de-emphasis per port. C10 is for RX#1 and C11 is for RX#2. These parts are listed as optional on the schematic, and like many things from CAT, they don't tell you the damn value... I also looked at the audio chain... I see they have taken my advice for the output coupling capacitor value, but the input cap is too small. It's a .1, and it feeds a 10K pot, and the wiper feeds a 10K input resistor. Depending on the setting of the input control, this could result in a .1 feeding 5K shunt resistance. Doing the math, this equates to a low end roll that could be as high as 318 Hz. In my opinion, a .1 uF cap is TOO SMALL. I'd change it to a .47 uF bringing the corner to 67 Hz. My recommendations: Change C8 and C9 to something larger than .1uFI recommend nothing smaller than a .47 uF _Non-Polarized_ capacitor. Install C10 or C11 with (depending on which port of the controller you are using and what audio is being delivered) whatever CAT tells you to install for de-emphasis. I recommend a .05 uF which puts the de-emphasis corner at 96 Hz. 7 years ago many folks complained about the terrible audio on CAT's high-end controller, the CAT-1000. Jim Hartzell, Jay Farmer and I did some research and created the following article: http://www.repeater-builder.com/cat-auto/cat-1000-audio.html The result was CAT changed the values of the capacitors in their production to values that are similar to those suggested in the article. So, now we find out you only get the /good audio chain/ *if* you buy the more expensive controller. What a crock Let us know how you make out, Jim... Kevin Custer Jim Brown wrote: This may be out in left field, but I have built several repeaters using the CAT300 controller (not the CAT200) and the 300 had no way to de-emphasize the discriminator audio. I have used an external series 15 K and shunt .22 cap to supply the discriminator audio to the CAT300 and it sounds great. Maybe one of your repeaters does not have the de-emphasis circuit installed, or if it is available on the CAT200, maybe it is not set in the right mode. 73 - Jim W5ZIT */Eric Lemmon [EMAIL PROTECTED]/* wrote: Subject: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS Hi Guys, A question for the MICOR fans that may have experienced a similar dilemma I am having with one of our three Micor Repeaters. All three are Micor VHF Bases, converted to repeater duty using the information I obtained from this group. All three have Cat 200 Controllers and unless I have missed something all are wired the same. When a weak signal, like from a portable radio or a station far away comes in I have quite a bit of background (white noise). I have noticed that if I listen to the audio from the Micor Speaker, it appears to me that much of the white noise is gone and the signal is much more understandable. Now this audio test is being performed with the TX on, so I have determined that there is no noticeable desense. The first thing I did was check the input audio into the Cat200 and make sure the voltages were set to the book, which they were. I have also taken into consideration that the Micor Speaker may reproduce the audio better than the HT or Mobile, but there is still enough difference that I wish the repeater audio, on weak signals only, sounded as good as the Micor RX direct to the speaker. I am using Discriminator Audio on all the repeaters and have the controller set properly for that. The only way to explain a weak signal is the background seems to be pumped up. Any ideas I will look into on my next trip to Pa. 73 Jim KA2AJH Wellsville, NY
[Repeater-Builder] Done!!
Well everyone, it's DONE! The N9WYS 900 MHz repeater station is finally built and ready to go on-the-air!! I want to thank EVERYONE here who was so patient, understanding and helpful during my arduous journey in building this machine... The final configuration is as follows: Glenayre GL-series paging station cabinet, utilizing the 26VDC power supply Motorola MaxTrac (800 MHz converted to receive at 902) receiver Motorola GTX exciter/transmitter Com-Spec TP-3200 controller panel Custom-made duplexer/isolator (many thanks to Jeff DePolo!!) Motorola STF2520A Power Amplifier, modified for use at 927 MHz (circulator removed) The station is making ~98W at the antenna port exiting the cabinet, so I can't complain one bit... I wanted a 100W machine, and I got one! Now all I need is to haul it to the tower site and get it installed - and I'm working on the logistics of that as I write. grin BTW - if anyone wants to see photos, let me know. (Or I can post them at the group site, if that is OK...) One last, HUGE thank you goes to Ryan - K9ZOE, who allowed me to place his station on the air on my pair until I could complete the construction on my own machine! Once the machine actually goes on-the-air, I'll post again. Thanks all es VY 73! Mark - N9WYS
[Repeater-Builder] Re: zetron 38a
Thanks for the help. Need a little more clarification. I have never used one of these before, so I don't want to blow it up. I have a chip that is stackedI suppose this is the one. I took it apart and wouldn't you know it, I managed to turn the chip socket with the smaller chip inside around, so I am not sure of its orientation. It has a cut out on the small chip inside the socket. I suppose this marks pin one and I would place the large chip with its dot in the same direction. Now, I have an empty chip space. What socket does it go into... U15 or U16should have marked itdumb. Sorry for the bother, but a little bit of orientation will keep me from blowing it up... Thanks ron --- In Repeater-Builder@yahoogroups.com, Maire-Radios maire- [EMAIL PROTECTED] wrote: take out the chip with the battery and unplug the chip from the battery give it 3 mins or so and put it back should default. - Original Message - From: rwjohn49 To: Repeater-Builder@yahoogroups.com Sent: Saturday, November 03, 2007 9:11 PM Subject: [Repeater-Builder] zetron 38a Folks, I just got a Zetron 38A at a hamfest. Works fine in the repeater but I have tried the password code and no results. It is listed in the book as 12123#. Someone must have changed it... What do I do now? Can it be set back to a factory default? thanks, ron
RE: [Repeater-Builder] Crystals Motorola etc
Joe, I don't see a connection between how long the order takes and whether or not the crystals are flawless. Knowing that a properly-made and -compensated crystal takes time, I'd shy away from a company that has a very short turnaround. Perhaps the longer turnaround time with orders at ICM is due to ICM getting a lot of new business from disgruntled customers of other crystal suppliers. If you ever get the opportunity to tour the Bomar crystal plant, do so, and take plenty of pictures and keep careful notes. Follow a particular crystal order through the process from order-taking to shipment. Then, do the same thing at ICM. Write an article about your findings, and draw some conclusions. I am quite certain it will be interesting! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of MCH Sent: Saturday, November 03, 2007 9:39 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Crystals Motorola etc I just went (actually, AM GOING) through an order with ICM. Boy have they changed in the last 10 years. Orders take much longer than they used to. I went with ICM because this particular order I wanted to be flawless. I should have stuck with Bomar. Joe M. Jim Brown wrote: I use Bomar these days for crystals for the ham bands. I have had good luck installing them myself and re-adjusting them in a year or so back to the right frequency. I recently worked on a GE Delta radio that had been crystaled using CUMEX and found the receive crystal had drifted over 2 kHz in the several years it had been in service. It was so far off it would not adust back to the original frequency until I ran the adjustment slug on down through the coil form and added another slug on top of it. Now with two slugs in the coil, it wound up back on frequency. I don't know if it will continue to drift, or if it has settled down, but for now it is working just fine. I used Marden for crystals until I got into a beef with them on a receive frequency and gave up after sending an operating crystal back to them a couple of times and telling them what frequency it operated on, and them sending it back and telling me what frequency they thought it operated on. 73 - Jim W5ZIT [EMAIL PROTECTED] mailto:w7hsg%40comcast.net wrote: Hi All Looking for information on who makes crystals for channel elements. Micor's and Mitrek Yes, I know that International makes them but the price is high. I have had good luck putting crystals in old channel elements and changing the caps as necessary to achieve reasonable stability. Used to use CUMEX in El Paso but they seem to be gone Ralph, W7HSG From: Kris Kirby [EMAIL PROTECTED] mailto:kris%40catonic.us To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Re: UHF Radio recommendations ?? Date: Sat, 3 Nov 2007 23:32:48 + On Fri, 2 Nov 2007, wb6ymh wrote: The 30 watt version is a better radio for repeater service since all solid state transmitters are very inefficient when run below their designed output. A 30 watt Mitrek running at 15 watts will probably last forever, but a 50 watt Mitrek running at 20 watts gets way too hot for my tastes. It would probably be ok with a fan, but I really didn't want a fan for numerous reasons. Well the radio is only specified to run a certain percentage in transmit anyway, but at this point, you can probably get a dump-truck load of Mitreks for the asking. That will give you enough radios to keep the repeater running until Doomsday. All you need is a few channel elements, and you can skip using lightning protection altogether. If a Mitrek falls in the forest, does it make a noise? -- Kris Kirby, KE4AHR [EMAIL PROTECTED] mailto:kris%40catonic.us But remember, with no superpowers comes no responsibility. --rly __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com http://mail.yahoo.com
Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
On the CAT200B manual I have, page 6-2 tells all about adding C10 and/or C11, and the value they supply is 0.0047uF. Don't chastise them so hastily. Engage eyes before shifting fingers! They probably designed the audio stage to reject sub-audible tones. The audio response is perfectly adequate when driven from a de-emphasized audio source and feeding a transmitter that will follow it with pre-emphasis. In my case, using MaxTracs, I just use the constant amplitude Headset Audio available on the front panel RJ45 MIC jack, and feed audio into the MIC input on the same jack. As both of these already have sub-audible audio filtered out, the controller has no problem with the audio. Using a 0.05uF cap for de-emphasis will likely make it take effect way too early, considering everything else in the system. As was mentioned earlier, if the Micor circuitry provides flat audio in and out, it is up to the person doing the controller integration to add the appropriate pre- and de-emphasis. Bob M. == --- Kevin Custer [EMAIL PROTECTED] wrote: I downloaded the manual on the CAT-200 and looked The CAT-200B has the ability to do de-emphasis, but, it's not as simple as flipping a dip switch; you must install a capacitor for adding de-emphasis per port. C10 is for RX#1 and C11 is for RX#2. These parts are listed as optional on the schematic, and like many things from CAT, they don't tell you the damn value... I also looked at the audio chain... I see they have taken my advice for the output coupling capacitor value, but the input cap is too small. It's a .1, and it feeds a 10K pot, and the wiper feeds a 10K input resistor. Depending on the setting of the input control, this could result in a .1 feeding 5K shunt resistance. Doing the math, this equates to a low end roll that could be as high as 318 Hz. In my opinion, a .1 uF cap is TOO SMALL. I'd change it to a .47 uF bringing the corner to 67 Hz. My recommendations: Change C8 and C9 to something larger than .1uFI recommend nothing smaller than a .47 uF _Non-Polarized_ capacitor. Install C10 or C11 with (depending on which port of the controller you are using and what audio is being delivered) whatever CAT tells you to install for de-emphasis. I recommend a .05 uF which puts the de-emphasis corner at 96 Hz. 7 years ago many folks complained about the terrible audio on CAT's high-end controller, the CAT-1000. Jim Hartzell, Jay Farmer and I did some research and created the following article: http://www.repeater-builder.com/cat-auto/cat-1000-audio.html The result was CAT changed the values of the capacitors in their production to values that are similar to those suggested in the article. So, now we find out you only get the /good audio chain/ *if* you buy the more expensive controller. What a crock Let us know how you make out, Jim... Kevin Custer Jim Brown wrote: This may be out in left field, but I have built several repeaters using the CAT300 controller (not the CAT200) and the 300 had no way to de-emphasize the discriminator audio. I have used an external series 15 K and shunt .22 cap to supply the discriminator audio to the CAT300 and it sounds great. Maybe one of your repeaters does not have the de-emphasis circuit installed, or if it is available on the CAT200, maybe it is not set in the right mode. 73 - Jim W5ZIT */Eric Lemmon [EMAIL PROTECTED]/* wrote: Subject: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS Hi Guys, A question for the MICOR fans that may have experienced a similar dilemma I am having with one of our three Micor Repeaters. All three are Micor VHF Bases, converted to repeater duty using the information I obtained from this group. All three have Cat 200 Controllers and unless I have missed something all are wired the same. When a weak signal, like from a portable radio or a station far away comes in I have quite a bit of background (white noise). I have noticed that if I listen to the audio from the Micor Speaker, it appears to me that much of the white noise is gone and the signal is much more understandable. Now this audio test is being performed with the TX on, so I have determined that there is no noticeable desense. The first thing I did was check the input audio into the Cat200 and make sure the voltages were set to the book, which they were. I have also taken into consideration that the Micor Speaker may reproduce the audio better than the HT or Mobile, but there is still enough difference that I wish the repeater audio, on weak signals only, sounded as good as the Micor RX direct to the speaker. I am using Discriminator Audio on all the repeaters and have the controller set properly for that. The only way to explain a weak
RE: [Repeater-Builder] Crystals Motorola etc
My last few crystal orders went to West Crystal (www.westcrystal.com) in BC, Canada. In the 80's and early 90's I ordered from Bomar exclusively, and then started running into problems and switched to ICM. I was very happy with ICM for the next ten years or so, but their prices started to get pretty steep so I decided to try West Crystal on the recommendation of Dave KA9FUR and several others on this list and I've been pleased thus far. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Eric Lemmon Sent: Sunday, November 04, 2007 10:51 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Crystals Motorola etc Joe, I don't see a connection between how long the order takes and whether or not the crystals are flawless. Knowing that a properly-made and -compensated crystal takes time, I'd shy away from a company that has a very short turnaround. Perhaps the longer turnaround time with orders at ICM is due to ICM getting a lot of new business from disgruntled customers of other crystal suppliers. If you ever get the opportunity to tour the Bomar crystal plant, do so, and take plenty of pictures and keep careful notes. Follow a particular crystal order through the process from order-taking to shipment. Then, do the same thing at ICM. Write an article about your findings, and draw some conclusions. I am quite certain it will be interesting! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of MCH Sent: Saturday, November 03, 2007 9:39 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Crystals Motorola etc I just went (actually, AM GOING) through an order with ICM. Boy have they changed in the last 10 years. Orders take much longer than they used to. I went with ICM because this particular order I wanted to be flawless. I should have stuck with Bomar. Joe M. Jim Brown wrote: I use Bomar these days for crystals for the ham bands. I have had good luck installing them myself and re-adjusting them in a year or so back to the right frequency. I recently worked on a GE Delta radio that had been crystaled using CUMEX and found the receive crystal had drifted over 2 kHz in the several years it had been in service. It was so far off it would not adust back to the original frequency until I ran the adjustment slug on down through the coil form and added another slug on top of it. Now with two slugs in the coil, it wound up back on frequency. I don't know if it will continue to drift, or if it has settled down, but for now it is working just fine. I used Marden for crystals until I got into a beef with them on a receive frequency and gave up after sending an operating crystal back to them a couple of times and telling them what frequency it operated on, and them sending it back and telling me what frequency they thought it operated on. 73 - Jim W5ZIT [EMAIL PROTECTED] mailto:w7hsg%40comcast.net mailto:w7hsg%40comcast.net wrote: Hi All Looking for information on who makes crystals for channel elements. Micor's and Mitrek Yes, I know that International makes them but the price is high. I have had good luck putting crystals in old channel elements and changing the caps as necessary to achieve reasonable stability. Used to use CUMEX in El Paso but they seem to be gone Ralph, W7HSG From: Kris Kirby [EMAIL PROTECTED] mailto:kris%40catonic.us mailto:kris%40catonic.us To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Re: UHF Radio recommendations ?? Date: Sat, 3 Nov 2007 23:32:48 + On Fri, 2 Nov 2007, wb6ymh wrote: The 30 watt version is a better radio for repeater service since all solid state transmitters are very inefficient when run below their designed output. A 30 watt Mitrek running at 15 watts will probably last forever, but a 50 watt Mitrek running at 20 watts gets way too hot for my tastes. It would probably be ok with a fan, but I really didn't want a fan for numerous reasons. Well the radio is only specified to run a certain percentage in transmit anyway, but at this point, you can probably get a dump-truck load of Mitreks for the asking. That will give you enough radios to keep the repeater running until Doomsday. All you need is a few channel elements, and you can skip using lightning protection altogether. If a Mitrek falls in the forest, does it make a noise? -- Kris Kirby, KE4AHR [EMAIL PROTECTED]
Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
I am using a CAT 200B controller on a 222 mhz repeater made from a Micor mobile that I converted to 222 mhz and a UHF GE Delta-s for a remote base radio. I am using discriminator audio from both radios with the 0047uf C10 and C11 installed, everyone says that the repeater audio is excellent. - Original Message - From: Bob M.mailto:[EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.commailto:Repeater-Builder@yahoogroups.com Sent: Sunday, November 04, 2007 9:14 AM Subject: Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS On the CAT200B manual I have, page 6-2 tells all about adding C10 and/or C11, and the value they supply is 0.0047uF. Don't chastise them so hastily. Engage eyes before shifting fingers! They probably designed the audio stage to reject sub-audible tones. The audio response is perfectly adequate when driven from a de-emphasized audio source and feeding a transmitter that will follow it with pre-emphasis. In my case, using MaxTracs, I just use the constant amplitude Headset Audio available on the front panel RJ45 MIC jack, and feed audio into the MIC input on the same jack. As both of these already have sub-audible audio filtered out, the controller has no problem with the audio. Using a 0.05uF cap for de-emphasis will likely make it take effect way too early, considering everything else in the system. As was mentioned earlier, if the Micor circuitry provides flat audio in and out, it is up to the person doing the controller integration to add the appropriate pre- and de-emphasis. Bob M. == --- Kevin Custer [EMAIL PROTECTED]mailto:[EMAIL PROTECTED] wrote: I downloaded the manual on the CAT-200 and looked The CAT-200B has the ability to do de-emphasis, but, it's not as simple as flipping a dip switch; you must install a capacitor for adding de-emphasis per port. C10 is for RX#1 and C11 is for RX#2. These parts are listed as optional on the schematic, and like many things from CAT, they don't tell you the damn value... I also looked at the audio chain... I see they have taken my advice for the output coupling capacitor value, but the input cap is too small. It's a .1, and it feeds a 10K pot, and the wiper feeds a 10K input resistor. Depending on the setting of the input control, this could result in a .1 feeding 5K shunt resistance. Doing the math, this equates to a low end roll that could be as high as 318 Hz. In my opinion, a .1 uF cap is TOO SMALL. I'd change it to a .47 uF bringing the corner to 67 Hz. My recommendations: Change C8 and C9 to something larger than .1uF I recommend nothing smaller than a .47 uF _Non-Polarized_ capacitor. Install C10 or C11 with (depending on which port of the controller you are using and what audio is being delivered) whatever CAT tells you to install for de-emphasis. I recommend a .05 uF which puts the de-emphasis corner at 96 Hz. 7 years ago many folks complained about the terrible audio on CAT's high-end controller, the CAT-1000. Jim Hartzell, Jay Farmer and I did some research and created the following article: http://www.repeater-builder.com/cat-auto/cat-1000-audio.htmlhttp://www.repeater-builder.com/cat-auto/cat-1000-audio.html The result was CAT changed the values of the capacitors in their production to values that are similar to those suggested in the article. So, now we find out you only get the /good audio chain/ *if* you buy the more expensive controller. What a crock Let us know how you make out, Jim... Kevin Custer Jim Brown wrote: This may be out in left field, but I have built several repeaters using the CAT300 controller (not the CAT200) and the 300 had no way to de-emphasize the discriminator audio. I have used an external series 15 K and shunt .22 cap to supply the discriminator audio to the CAT300 and it sounds great. Maybe one of your repeaters does not have the de-emphasis circuit installed, or if it is available on the CAT200, maybe it is not set in the right mode. 73 - Jim W5ZIT */Eric Lemmon [EMAIL PROTECTED]mailto:[EMAIL PROTECTED]/* wrote: Subject: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS Hi Guys, A question for the MICOR fans that may have experienced a similar dilemma I am having with one of our three Micor Repeaters. All three are Micor VHF Bases, converted to repeater duty using the information I obtained from this group. All three have Cat 200 Controllers and unless I have missed something all are wired the same. When a weak signal, like from a portable radio or a station far away comes in I have quite a bit of background (white noise). I have noticed
Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
On Nov 4, 2007, at 9:35 AM, James H Vernetti wrote: everyone says that the repeater audio is excellent. Not trying to sound too obnoxious here, and this is just a general comment, not necessarily meant to reflect this particular controller or setup but... *I've heard hams say that a LOT of things that are done wrong at the audio level sound great.* There's a difference between subjective comments and objective measurements. The only way to know for sure that your repeater is right is to sweep it. Or rely on the engineering that someone else did who did sweep theirs when they set it up the same way. For a quick-and-dirty sweep, a series of tones from the low end to the high end (as many as you like) and seeing if the repeater repeats them at relatively the same deviation level, is usually good enough for this test. A good system won't tilt that audio toward either end of the 300-3000 Hz AF spectrum. The other way to tell that's even easier: Listen to stations on the input and output of the repeater alternately with the reverse button on a radio with a good high-quality speaker and plenty of audio in a quiet listening environment. If you can't tell the difference between the input and repeated signal (assuming of course that the stations you've chosen to monitor in this way aren't over-deviated, etc) then the repeater is done right. If you hear any colorization of the audio (more bass, tinny, compressed, or a different deviation level, which manifests itself as a change in audio level at your speaker if all you are doing is hitting the reverse button)... it's not done right. Pretty easy to test, harder to get right in practice. To get it right, there are a couple of camps/religions. Either one can effectively do the job, if enough attention is paid to detail. -- Nate Duehr, WY0X [EMAIL PROTECTED]
Re: [Repeater-Builder] Crystals Motorola etc
Fine. If they have to take longer to provide the product, don't tell me delivery will be 4 weeks than take longer. The apology letter I received from them said nothing about a backlog of orders. As for the flawless part, I did not directly relate that to the time. I said I went with them due to their reputation. That is the reason why I didn't order from Bomar. In all the orders from Bomar, they always took how long they said. While I've never had a problem with them, I wanted to take out the extra 'insurance' of purchasing from ICM. I wasn't aware of the fact that the delivery time would suffer as much as it has. Joe M. Eric Lemmon wrote: Joe, I don't see a connection between how long the order takes and whether or not the crystals are flawless. Knowing that a properly-made and -compensated crystal takes time, I'd shy away from a company that has a very short turnaround.
RE: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
Thanks for the research Kevin. This Cat 200 is a good one to start with. I did not do the original install, so I will check the values. Mr. Lightning as not been good to this site, so this is the 3rd repeater the controller has been on. The other two were Micor Mobiles. Hope to get the associated link up before winter and I will make these modifications and post the results. 73 JIM KA2AJH _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Kevin Custer Sent: Sunday, November 04, 2007 8:45 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS I downloaded the manual on the CAT-200 and looked The CAT-200B has the ability to do de-emphasis, but, it's not as simple as flipping a dip switch; you must install a capacitor for adding de-emphasis per port. C10 is for RX#1 and C11 is for RX#2. These parts are listed as optional on the schematic, and like many things from CAT, they don't tell you the damn value... I also looked at the audio chain... I see they have taken my advice for the output coupling capacitor value, but the input cap is too small. It's a .1, and it feeds a 10K pot, and the wiper feeds a 10K input resistor. Depending on the setting of the input control, this could result in a .1 feeding 5K shunt resistance. Doing the math, this equates to a low end roll that could be as high as 318 Hz. In my opinion, a .1 uF cap is TOO SMALL. I'd change it to a .47 uF bringing the corner to 67 Hz. My recommendations: Change C8 and C9 to something larger than .1uFI recommend nothing smaller than a .47 uF Non-Polarized capacitor. Install C10 or C11 with (depending on which port of the controller you are using and what audio is being delivered) whatever CAT tells you to install for de-emphasis. I recommend a .05 uF which puts the de-emphasis corner at 96 Hz. 7 years ago many folks complained about the terrible audio on CAT's high-end controller, the CAT-1000. Jim Hartzell, Jay Farmer and I did some research and created the following article: http://www.repeater http://www.repeater-builder.com/cat-auto/cat-1000-audio.html -builder.com/cat-auto/cat-1000-audio.html The result was CAT changed the values of the capacitors in their production to values that are similar to those suggested in the article. So, now we find out you only get the good audio chain *if* you buy the more expensive controller. What a crock Let us know how you make out, Jim... Kevin Custer Jim Brown wrote: This may be out in left field, but I have built several repeaters using the CAT300 controller (not the CAT200) and the 300 had no way to de-emphasize the discriminator audio. I have used an external series 15 K and shunt .22 cap to supply the discriminator audio to the CAT300 and it sounds great. Maybe one of your repeaters does not have the de-emphasis circuit installed, or if it is available on the CAT200, maybe it is not set in the right mode. 73 - Jim W5ZIT Eric Lemmon mailto:[EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Subject: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS Hi Guys, A question for the MICOR fans that may have experienced a similar dilemma I am having with one of our three Micor Repeaters. All three are Micor VHF Bases, converted to repeater duty using the information I obtained from this group. All three have Cat 200 Controllers and unless I have missed something all are wired the same. When a weak signal, like from a portable radio or a station far away comes in I have quite a bit of background (white noise). I have noticed that if I listen to the audio from the Micor Speaker, it appears to me that much of the white noise is gone and the signal is much more understandable. Now this audio test is being performed with the TX on, so I have determined that there is no noticeable desense. The first thing I did was check the input audio into the Cat200 and make sure the voltages were set to the book, which they were. I have also taken into consideration that the Micor Speaker may reproduce the audio better than the HT or Mobile, but there is still enough difference that I wish the repeater audio, on weak signals only, sounded as good as the Micor RX direct to the speaker. I am using Discriminator Audio on all the repeaters and have the controller set properly for that. The only way to explain a weak signal is the background seems to be pumped up. Any ideas I will look into on my next trip to Pa. 73 Jim KA2AJH Wellsville, NY
Re: [Repeater-Builder] Micor Audio on VERY WEAK SIGNALS
On Nov 4, 2007, at 1:21 PM, Jim Cicirello wrote: Thanks for the research Kevin. This Cat 200 is a good one to start with. I did not do the original install, so I will check the values. Mr. Lightning as not been good to this site, so this is the 3rd repeater the controller has been on. The other two were Micor Mobiles. Hope to get the associated link up before winter and I will make these modifications and post the results. Hopefully you're also making modifications to the lightning protection and/or grounding systems? :-) -- Nate Duehr, WY0X [EMAIL PROTECTED]
Re: [Repeater-Builder] Crystals Motorola etc
Just out of curiosity, how long were you quotes, and how long did it actually take? At 10:30 AM 11/04/07, you wrote: Fine. If they have to take longer to provide the product, don't tell me delivery will be 4 weeks than take longer. The apology letter I received from them said nothing about a backlog of orders. As for the flawless part, I did not directly relate that to the time. I said I went with them due to their reputation. That is the reason why I didn't order from Bomar. In all the orders from Bomar, they always took how long they said. While I've never had a problem with them, I wanted to take out the extra 'insurance' of purchasing from ICM. I wasn't aware of the fact that the delivery time would suffer as much as it has. Joe M. Eric Lemmon wrote: Joe, I don't see a connection between how long the order takes and whether or not the crystals are flawless. Knowing that a properly-made and -compensated crystal takes time, I'd shy away from a company that has a very short turnaround. Yahoo! Groups Links
Re: [Repeater-Builder] Re: zetron 38a
Be sure to align pin 1 with the socket and with the Dallas Semiconductor Battery Backup and the memory chip and plug them into U15. My units do not even have sockets installed in U16, but I suspect the two locations are pretty much in parallel except for an address line to give the unit more ram, or to use a smaller capacity ram chip and use two instead of the one. I happen to have a unit down waiting for a new battery backup chip, and they are hard to find. The jobbers have them but one wants a minimum order of $1000 and the other one I checked out wanted $88 for a minimum order. My units are over 15 years old and well beyond the battery life of the Dallas Semiconductor backup unit. 73 - Jim W5ZIT rwjohn49 [EMAIL PROTECTED] wrote: Thanks for the help. Need a little more clarification. I have never used one of these before, so I don't want to blow it up. I have a chip that is stackedI suppose this is the one. I took it apart and wouldn't you know it, I managed to turn the chip socket with the smaller chip inside around, so I am not sure of its orientation. It has a cut out on the small chip inside the socket. I suppose this marks pin one and I would place the large chip with its dot in the same direction. Now, I have an empty chip space. What socket does it go into... U15 or U16should have marked itdumb. Sorry for the bother, but a little bit of orientation will keep me from blowing it up... Thanks ron --- In Repeater-Builder@yahoogroups.com, Maire-Radios maire- [EMAIL PROTECTED] wrote: take out the chip with the battery and unplug the chip from the battery give it 3 mins or so and put it back should default. - Original Message - From: rwjohn49 To: Repeater-Builder@yahoogroups.com Sent: Saturday, November 03, 2007 9:11 PM Subject: [Repeater-Builder] zetron 38a Folks, I just got a Zetron 38A at a hamfest. Works fine in the repeater but I have tried the password code and no results. It is listed in the book as 12123#. Someone must have changed it... What do I do now? Can it be set back to a factory default? thanks, ron __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
Re: [Repeater-Builder] Re: zetron 38a
Depending on the type of Dallas chip you can add an external battery to them. There are instructions on how to do it on the internet. I ran across them when looking for a way to fix a problem I was having with the bios on a Sun server. A little search on Google might bring you some instructions. Vern KI4ONW On Sun, 4 Nov 2007 19:18:32 -0800 (PST) Jim Brown [EMAIL PROTECTED] wrote: Be sure to align pin 1 with the socket and with the Dallas Semiconductor Battery Backup and the memory chip and plug them into U15. My units do not even have sockets installed in U16, but I suspect the two locations are pretty much in parallel except for an address line to give the unit more ram, or to use a smaller capacity ram chip and use two instead of the one. I happen to have a unit down waiting for a new battery backup chip, and they are hard to find. The jobbers have them but one wants a minimum order of $1000 and the other one I checked out wanted $88 for a minimum order. My units are over 15 years old and well beyond the battery life of the Dallas Semiconductor backup unit. 73 - Jim W5ZIT rwjohn49 [EMAIL PROTECTED] wrote: Thanks for the help. Need a little more clarification. I have never used one of these before, so I don't want to blow it up. I have a chip that is stackedI suppose this is the one. I took it apart and wouldn't you know it, I managed to turn the chip socket with the smaller chip inside around, so I am not sure of its orientation. It has a cut out on the small chip inside the socket. I suppose this marks pin one and I would place the large chip with its dot in the same direction. Now, I have an empty chip space. What socket does it go into... U15 or U16should have marked itdumb. Sorry for the bother, but a little bit of orientation will keep me from blowing it up... Thanks ron --- In Repeater-Builder@yahoogroups.com, Maire-Radios maire- [EMAIL PROTECTED] wrote: take out the chip with the battery and unplug the chip from the battery give it 3 mins or so and put it back should default. - Original Message - From: rwjohn49 To: Repeater-Builder@yahoogroups.com Sent: Saturday, November 03, 2007 9:11 PM Subject: [Repeater-Builder] zetron 38a Folks, I just got a Zetron 38A at a hamfest. Works fine in the repeater but I have tried the password code and no results. It is listed in the book as 12123#. Someone must have changed it... What do I do now? Can it be set back to a factory default? thanks, ron __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
RE: [Repeater-Builder] VSWR Chart for Bird
1 + square root (r/f) SWR= _ 1 - square root (r/f) where r = reflected power f = forward power 73 Gary K4FMX from: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9wys Sent: Wednesday, October 31, 2007 6:07 PM To: Repeater-Builder@yahoogroups.com; [EMAIL PROTECTED] Subject: [Repeater-Builder] VSWR Chart for Bird Does anyone have a VSWR chart for the Bird wattmeter (preferably the 4410, since that's what I have - but I'm not sure there would be any difference) that they would be willing to share with me? I bought my meter used and it came with neither manual nor chart. Thanks, Mark - N9WYS
Re: [Repeater-Builder] Re: zetron 38a
If anybody wants to do a photo article on recovering a Zetron (i.e. getting back to the default password) or on replacing the battery, or adding an outside battery, let me know. Mike co-web-master at repeater-builder At 07:20 PM 11/04/07, you wrote: Depending on the type of Dallas chip you can add an external battery to them. There are instructions on how to do it on the internet. I ran across them when looking for a way to fix a problem I was having with the bios on a Sun server. A little search on Google might bring you some instructions. Vern KI4ONW On Sun, 4 Nov 2007 19:18:32 -0800 (PST) Jim Brown [EMAIL PROTECTED] wrote: Be sure to align pin 1 with the socket and with the Dallas Semiconductor Battery Backup and the memory chip and plug them into U15. My units do not even have sockets installed in U16, but I suspect the two locations are pretty much in parallel except for an address line to give the unit more ram, or to use a smaller capacity ram chip and use two instead of the one. I happen to have a unit down waiting for a new battery backup chip, and they are hard to find. The jobbers have them but one wants a minimum order of $1000 and the other one I checked out wanted $88 for a minimum order. My units are over 15 years old and well beyond the battery life of the Dallas Semiconductor backup unit. 73 - Jim W5ZIT rwjohn49 [EMAIL PROTECTED] wrote: Thanks for the help. Need a little more clarification. I have never used one of these before, so I don't want to blow it up. I have a chip that is stackedI suppose this is the one. I took it apart and wouldn't you know it, I managed to turn the chip socket with the smaller chip inside around, so I am not sure of its orientation. It has a cut out on the small chip inside the socket. I suppose this marks pin one and I would place the large chip with its dot in the same direction. Now, I have an empty chip space. What socket does it go into... U15 or U16should have marked itdumb. Sorry for the bother, but a little bit of orientation will keep me from blowing it up... Thanks ron --- In Repeater-Builder@yahoogroups.com, Maire-Radios maire- [EMAIL PROTECTED] wrote: take out the chip with the battery and unplug the chip from the battery give it 3 mins or so and put it back should default. - Original Message - From: rwjohn49 To: Repeater-Builder@yahoogroups.com Sent: Saturday, November 03, 2007 9:11 PM Subject: [Repeater-Builder] zetron 38a Folks, I just got a Zetron 38A at a hamfest. Works fine in the repeater but I have tried the password code and no results. It is listed in the book as 12123#. Someone must have changed it... What do I do now? Can it be set back to a factory default? thanks, ron
