Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
GOOD AFTERNOON kEVIN This last response is my thinking about the Mitrek and is why I asked the question earlier. If the Mitrek coils are the same as the Micor coils what factor would prohibit this being done. There is considerable work to change the coils but if the Micor coils are the same nothing would prohit a person from doing this. As I said earlier I know for a fact that the mid band receivers will not tune lower than 146 Mhz. Perhaps an occasional one would be found that would tune to 144.0 Mhz but not all. Thanks. 73 de Tom Manning, AF4UG - Original Message - From: Gmail - Kevin, Natalia, Stacey Rochelle To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 12:54 AM Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Hi, Is there a point inside the Mitrek that one can take the audio out to the controller (in this case a Link-Comm RLC-2A)? A low band Mitrek (33Mhz) I have downloaded the information fromLou's Mitrek Repeater Conversion and a couple of others which mention a schematic for emphasis before going into the controller. Taking the audio out on pin 11. I would like to leave this out if possible and feed directly? Regards and Merry Christmas Kev. - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 2:40 PM Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin -- I am using the free version of SPAMfighter. We are a community of 5.7 million users fighting spam. SPAMfighter has removed 1561 of my spam emails to date. Get the free SPAMfighter here: http://www.spamfighter.com/len The Professional version does not have this message
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Hello Kevin I did not see where you gave a price of a set of Micor receiver coils. Where might I find this info? Thanks. 73 de Tom Manning, AF4UG - Original Message - From: Eric Lemmon To: Repeater-Builder@yahoogroups.com Sent: Saturday, December 20, 2008 9:37 PM Subject: RE: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Kevin, Other than being physically smaller, I don't know of any helical resonator design issues that preclude your Micor mod from being adapted to the Mitrek. I am modifying some low-band Mitreks for 6m duty, but all that takes is a handful of capacitors. I have yet to address converting a high-band Mitrek to 2m, so I have no idea what issues may arise. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Kevin Custer Sent: Saturday, December 20, 2008 5:41 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin -- I am using the free version of SPAMfighter. We are a community of 5.7 million users fighting spam. SPAMfighter has removed 1561 of my spam emails to date. Get the free SPAMfighter here: http://www.spamfighter.com/len The Professional version does not have this message
RE: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Tom, The Mitrek coils are not the same as Micor coils. Not even close. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tom Manning Sent: Sunday, December 21, 2008 3:40 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) GOOD AFTERNOON kEVIN This last response is my thinking about the Mitrek and is why I asked the question earlier. If the Mitrek coils are the same as the Micor coils what factor would prohibit this being done. There is considerable work to change the coils but if the Micor coils are the same nothing would prohit a person from doing this. As I said earlier I know for a fact that the mid band receivers will not tune lower than 146 Mhz. Perhaps an occasional one would be found that would tune to 144.0 Mhz but not all. Thanks. 73 de Tom Manning, AF4UG - Original Message - From: Gmail - Kevin, Natalia, Stacey Rochelle mailto:spar...@gmail.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 12:54 AM Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Hi, Is there a point inside the Mitrek that one can take the audio out to the controller (in this case a Link-Comm RLC-2A)? A low band Mitrek (33Mhz) I have downloaded the information fromLou's Mitrek Repeater Conversion and a couple of others which mention a schematic for emphasis before going into the controller. Taking the audio out on pin 11. I would like to leave this out if possible and feed directly? Regards and Merry Christmas Kev. - Original Message - From: Kevin Custer mailto:kug...@kuggie.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 2:40 PM Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin I am using the Free version of SPAMfighter http://www.spamfighter.com/len We are a community of 5.7 million users fighting spam. SPAMfighter has removed 1561 of my spam emails to date. The Professional version does not have this message
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Tom Manning wrote: GOOD AFTERNOON kEVIN This last response is my thinking about the Mitrek and is why I asked the question earlier. If the Mitrek coils are the same as the Micor coils what factor would prohibit this being done. The coils are not the same, but I believe there is no reason I wouldn't be able to reproduce coils that would replicate the factory low split ones for the Mitrek. There is considerable work to change the coils but if the Micor coils are the same nothing would prohit a person from doing this. As I said earlier I know for a fact that the mid band receivers will not tune lower than 146 Mhz. Perhaps an occasional one would be found that would tune to 144.0 Mhz but not all. Thanks. 73 de Tom Manning, AF4UG I need to look at a VHF Mitrek and see if I can build replacements and at what cost. I did not see where you gave a price of a set of Micor receiver coils. Where might I find this info? Thanks. 73 de Tom Manning, AF4UG The Holiday Special price of the VHF MICOR redo is laid out in the link below: http://www.repeater-builder.com/rbtip/hs-coilinstructions.html Kevin
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
This probably will not work on the Mitrek since it may not use slugs to tune the coil, but I had a problem with a crystal on a Delta radio that would not go low enough in frequency. I removed the slug from the F2 coil and ran the slug for the F1 coil through max inductance and then added the second slug on top of the first. The combined slugs allowed me to net the crystal. 73 - Jim W5ZIT --- On Sat, 12/20/08, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) To: Repeater-Builder@yahoogroups.com Date: Saturday, December 20, 2008, 9:27 AM Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Kevin Custer Sent: Friday, December 19, 2008 9:30 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver conversion from W3KKC Tom, Okay I guess I should ask if replacement coils for the Mitrek are still available from Motorola, and if so, at what cost? If they are no longer available, or are cost prohibitive, send me one of your Mitrek receivers and I'll see if I can come up with a new set of coils that properly tune the whole 2M band. I guess at this point we should go to private email. Kevin Hello Kevin Thanks for your reply. Your statement is correct in that all of the receiver coils begin to tune at the bottom of their travel. I have even tuned two or three too far and they dropped out with the resulting work to retrieve the screws. When tuned as best I can for sens the s/n ratio is 1+uv at 12db sinad. The original frequency sens was less than 1uv-usually about .3uv for 12db sinad. Replacing the coils are about the only solution I know of for these high split VHF units. I have in the past replaced two sets of receiver coils with Motorola coils and found I have good sensitivity as before modification. The transmitters all tuned well on this split and gave rated or more power output. The Mitrek coils looked very much like the Micor coils. I have replaced probably a half dozen Micor receiver coils proscured from Motorola in the past 20 or so years. Thanks. 73 de Tom Manning, AF4UG - Original Message - From: Kevin Custer mailto:kug...@kuggie. com To: Repeater-Builder@ yahoogroups. com mailto:Repeater-Builder@ yahoogroups. com Sent: Thursday, December 18, 2008 10:02 PM Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver conversion from W3KKC Tom, You say you find similar operation on 4 or 5 units. By that do you mean they won't make book specification on any frequency below 146 MHz? If that is the case, I would believe something is wrong. I have seen many Mitrek high-band receivers that were tuned for 144 something and had very good sensitivity. Let me ask you this When tuned at 144.89, is the front-end tuning all one ended, or is there adjustment to spare? In other words, can you tune the front-end without the fear of the tuning screws falling into the casting? If you have room left to go lower in frequency, then the front-end is not the problem, and you'll need to look elsewhere for the lack of sensitivity. Another question - do these 4 or 5 units tune and make book spec sensitivity on their original high-band channel? I guess what I'm saying is I doubt the problem is the front-end helical resonators, but if there is a need for a conversion I'm not opposed to looking into making a modification available, if it is needed. If there are others on the list that have had good luck with the Mitrek on frequencies below 146 MHz, please chime in and let us know what you have and how well it works. Kevin Hello Kevin You are correct on your freqs for xmit and rcv. The Mitrek units I have will only tune receive to 146.00Mhz. This leaves more than one meg to go to meet tolerance on 144.890. I have tried 4 or 5 units and find similar operation of all. This is the reason for my question about the Micor coils working for Mitrek. Thanks. 73 de Tom Manning, AF4UG
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
I've had to add wire to the helicals on two Micors (UHF) to get them down to 447.75. It did the trick. It would certainly be worth a try. Chuck WB2EDV - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, December 20, 2008 10:27 AM Subject: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. 73, Eric Lemmon WB6FLY
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin
RE: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Kevin, Other than being physically smaller, I don't know of any helical resonator design issues that preclude your Micor mod from being adapted to the Mitrek. I am modifying some low-band Mitreks for 6m duty, but all that takes is a handful of capacitors. I have yet to address converting a high-band Mitrek to 2m, so I have no idea what issues may arise. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Kevin Custer Sent: Saturday, December 20, 2008 5:41 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Hi Eric, Kevin, Other than being physically smaller, I don't know of any helical resonator design issues that preclude your Micor mod from being adapted to the Mitrek. Oh okay good - - I was unsure if there was something I was missing; which could easily be the case. Thanks, Kevin
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
Hi, Is there a point inside the Mitrek that one can take the audio out to the controller (in this case a Link-Comm RLC-2A)? A low band Mitrek (33Mhz) I have downloaded the information fromLou's Mitrek Repeater Conversion and a couple of others which mention a schematic for emphasis before going into the controller. Taking the audio out on pin 11. I would like to leave this out if possible and feed directly? Regards and Merry Christmas Kev. - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 21, 2008 2:40 PM Subject: Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) Eric Lemmon wrote: Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. Eric, I would think a coil retro like what I make available for the MICOR will also work in the Mitrek. This approach would be way better than tacking some added wire onto the existing coil or modifying the screws in which I know that is a bad idea. Is there something special about the Mitrek front-end that you believe would prohibit such a conversion? It's been a while since I messed with the Mitrek but I don't remember anything that would prohibit the correct length coil to be installed... Kevin
