[Repeater-Builder] Antenna question for the forum.
Goodafternoon, Me and a friend are putting up a secondary VHF repeater and have a antenna question. Being we are on a budget but have looked at these 2 antennas as options. Diamond F22A monoband base or the Husler G6-144B Any pros or cons to these antennas and which would you choose or you have another option? Antenna will be mounted between 30-40' on multiuse rohn 45 tower fed with LMR-400 and subjected to typical Northeast USA weather North of NYC. Ofcourse if money wasn't an issue, I would prompt for a more durible antenna specifically suited for repeater use. We need to keep antenna size down to less then 10' in length and cost down as well. My choice was the Diamond F22A. It apears similiar in size and construction to the X-200 dual band and I have not had any issues with my current intallation. Any comments or suggestions??? 73, Steve - W2SXK [EMAIL PROTECTED]
[Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement
Eric, I tried that today and they positively will not work on the new type of crystal holders due to the way they are made since they cannot reliably make them work. They said they have done them in the past and lost money, wasted time, and angered customers in the process. John --- In Repeater-Builder@yahoogroups.com, Eric Lemmon [EMAIL PROTECTED] wrote: John, I suggest that you send the holders, with the old crystals, to International Crystal or to any competent crystal house. Simply instruct ICM to change the TX and RX from the existing frequencies to the desired new frequencies. It'll cost you about $100 for the pair, but you'll wind up with crystals that are guaranteed to work on the new channels. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John D. Sent: Thursday, January 24, 2008 5:28 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] EF Johnson CR1010 Crystal Replacement I have a CR1010 repeater that needs to have new crystals installed to change the frequency from 451.200 to 451.250 on the TX and 456.200 to 456.250 on the Rx. I tried to get crystals from EF Johnson and they said they no longer support this repeater. I then tried to get crystals from International Crystal and they said there were two types of holders new and old. They said that if I had the new type I would be unable to get crystals for them or they would never work. It just so happens this repeater has the new crystals so does anybody know where I can get a set of old crystal holders so I can change the freq. on this repeater? Also does anybody have any other good ideas on how I can proceed with this unit. Thanks
Re: [Repeater-Builder] Antenna question for the forum.
You'll hear this from others -- DO NOT use the LMR-400 cable in duplex situations. This subject comes up about every other week here. Chuck WB2EDV - Original Message - From: w2sxk [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, January 25, 2008 4:43 PM Subject: [Repeater-Builder] Antenna question for the forum. Goodafternoon, Me and a friend are putting up a secondary VHF repeater and have a antenna question. Being we are on a budget but have looked at these 2 antennas as options. Diamond F22A monoband base or the Husler G6-144B Any pros or cons to these antennas and which would you choose or you have another option? Antenna will be mounted between 30-40' on multiuse rohn 45 tower fed with LMR-400 and subjected to typical Northeast USA weather North of NYC. Ofcourse if money wasn't an issue, I would prompt for a more durible antenna specifically suited for repeater use. We need to keep antenna size down to less then 10' in length and cost down as well. My choice was the Diamond F22A. It apears similiar in size and construction to the X-200 dual band and I have not had any issues with my current intallation. Any comments or suggestions??? 73, Steve - W2SXK [EMAIL PROTECTED]
[Repeater-Builder] Re: Stupid Question about Db antennas.
--- In Repeater-Builder@yahoogroups.com, dallasreact112 [EMAIL PROTECTED] wrote: I have a question about the DB base antennas such as the DB-224, DB- 420, etc. As most of you know they consist of folded dipole trombones Bernie Parker K5BP Bernie There is no such thing as a stupid question . If you want to know something just ask. you might get some stupid answers but you might get the one you are looking for too. Dale N8SAC
Re: [Repeater-Builder] Re: Stupid Question about Db antennas.
At 08:27 AM 1/26/2008, you wrote: There is no such thing as a stupid question . If you want to know something just ask. you might get some stupid answers but you might get the one you are looking for too. Since we are in such a giving mood - let me ask something ... I have my hands on what I believe to be a Sinclair 224 Antenna. It is similar to a DB224, but has a smaller diameter mast, with thicker wall, and the harness is interior to the mast. The dipoles are fed through the interior of the bracket that holds the dipoles. Other than sweeping it with an antenna analyzer, and pulling each dipole bracket off to examine the interior for signs of arcing, is there any check I should do to be sure of the antenna being OK before we lift it? I have a best SWR of 1.12 at 147.1. I plan to use it at 145.150. The SWR per my MFJ 259 is 1.22 at 145.150. I have seen no sign of arcing inside the brackets. Ideas? Larry N5WLW
[Repeater-Builder] Re: Desense Problem on 222 MHz Repeater
--- In Repeater-Builder@yahoogroups.com, Eric Lemmon [EMAIL PROTECTED] wrote: I think you may have overlooked the fact that desense was observed even when a dummy load was connected directly to the output of the duplexer. That pretty much eliminates anything external to the repeater itself, doesn't it? - - I don't think I overlooked anything. I suggest that you re-read his posts. He said that he has 1 dB of desensitization when the system is tested on a dummy load, in excess of 15 dB of desensitization when running on one antenna and an improvement of about 6 dB when running on split antennas. I called his desensitization on the load minimal I don't see how you can call 1 dB equivalent to 15 dB and put the blame on the repeater equipment. Actually, there is one fact that is important, that there is still on the order of 9 dB of desensitization when running on split antennas. This alone strongly suggests that the repeater transmit RF is illuminating a passive IM source. [or is incident upon and mixing at a source that is illuminated by the DTV signal] Passive IM [PIM] can occur in many places. If the signal level of the interferer is high enough, it could occur in your antenna, in your coax, or in one of your connectors. Each could have a contribution. Deciding where is is occuring is the issue. Within your system or external? The industry is beginning to develop practices to deal with PIM. Andrew has published some information regarding PIM in transmission lines as has Amphenol with respect to PIM in connectors. See also Intermodulation in Coaxial Connectors, RF Design, September 1996. In this case, there are several possibilities to consider. If the spectrum analyzer can show the character of the noise that is causing the desensitization, and if that interference appears similar to to the DTV signal, then the task is to look for ways to identify its mix point and to defeat it. [I suggest that the source of degradation is a noise like interferer because it appears from the previous posts that the proper tests have been conducted to rule out a narrowband interferer.] I would also suggest swapping antennas when running split. If the results differ - it could give some guidance as to the proximity of the mix point to one or the other. Another test to run would be to measure the absolute level of the DTV signal at the transmission line to each of the two antennas. This will tell you how strong the signal is near your antennas. Remember that the wideband character of the DTV signal is going to affect the way that you measure it.
RE: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement
John, I stand corrected. I know that EFJ produced some oddball radios, but until now I have never heard of a crystal holder or channel element that could not be recrystalled by ICM. Live and learn! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John D. Sent: Friday, January 25, 2008 5:55 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement Eric, I tried that today and they positively will not work on the new type of crystal holders due to the way they are made since they cannot reliably make them work. They said they have done them in the past and lost money, wasted time, and angered customers in the process. John --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Eric Lemmon [EMAIL PROTECTED] wrote: John, I suggest that you send the holders, with the old crystals, to International Crystal or to any competent crystal house. Simply instruct ICM to change the TX and RX from the existing frequencies to the desired new frequencies. It'll cost you about $100 for the pair, but you'll wind up with crystals that are guaranteed to work on the new channels. 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 John D. Sent: Thursday, January 24, 2008 5:28 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] EF Johnson CR1010 Crystal Replacement I have a CR1010 repeater that needs to have new crystals installed to change the frequency from 451.200 to 451.250 on the TX and 456.200 to 456.250 on the Rx. I tried to get crystals from EF Johnson and they said they no longer support this repeater. I then tried to get crystals from International Crystal and they said there were two types of holders new and old. They said that if I had the new type I would be unable to get crystals for them or they would never work. It just so happens this repeater has the new crystals so does anybody know where I can get a set of old crystal holders so I can change the freq. on this repeater? Also does anybody have any other good ideas on how I can proceed with this unit. Thanks
[Repeater-Builder] Someone mentioned PIM
There is a light at the end of this tunnel... Sinclair Engineers really pushed the PIM issue out into the public eye when I first started dealing with them. The Sinclair Company has changed so much (make your own decisions) from those earlier days but you will notice most of their current antenna designs directly mention low PIM Engineered Designs. The reported IM within/from certain rf-connectors is the reason I no longer use Nickel Plated hard-line connectors found priced so reasonable on Ebay. :-( Sometimes a deal is not... back to the woodwork... and soaking wet with the rain. cheers, s. This alone strongly suggests that the repeater transmit RF is illuminating a passive IM source. [or is incident upon and mixing at a source that is illuminated by the DTV signal] Passive IM [PIM] can occur in many places. If the signal level of the interferer is high enough, it could occur in your antenna, in your coax, or in one of your connectors. Each could have a contribution. Deciding where is is occuring is the issue. Within your system or external? The industry is beginning to develop practices to deal with PIM. Andrew has published some information regarding PIM in transmission lines as has Amphenol with respect to PIM in connectors. See also Intermodulation in Coaxial Connectors, RF Design, September 1996.
[Repeater-Builder] Re: Notch and other Suck-Out Cavities
Re: Notch and other Suck-Out Cavities Many of the more common notch cavities are single port designs. I've also seen and setup some very creative applications using two-port band-pass bottles where the second port is terminated with a load. In one or two cases the terminated band-pass Cavity properly set up... solved a very pesky problem where the high-Q single port notch cavity layout did not. cheers, s. Steve Allred [EMAIL PROTECTED] wrote: Just make sure to pull the unused loop out of the cavity. Steve / K6SCA Gary Schafer [EMAIL PROTECTED] wrote: If you have an extra band pass cavity then you also have a notch cavity. Just connect a T to one port of the band pass cavity and ignore the other port on the cavity. This will work as a notch cavity for your testing. 73 Gary K4FMX
RE: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement
WONDERING OUT LOUD.WHO DID JOHNSON USE TO MAKE THEM IN THE FOIST PLACE??? MAYBE THEY CAN TELL YOU SINCE THEY OBVIOUSLY DIDN'T DO IT THEIR DAMN SELVES. SOME ONE HAD TO MFGR THE THINGS MDM --- Eric Lemmon [EMAIL PROTECTED] wrote: John, I stand corrected. I know that EFJ produced some oddball radios, but until now I have never heard of a crystal holder or channel element that could not be recrystalled by ICM. Live and learn! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John D. Sent: Friday, January 25, 2008 5:55 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement Eric, I tried that today and they positively will not work on the new type of crystal holders due to the way they are made since they cannot reliably make them work. They said they have done them in the past and lost money, wasted time, and angered customers in the process. John --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Eric Lemmon [EMAIL PROTECTED] wrote: John, I suggest that you send the holders, with the old crystals, to International Crystal or to any competent crystal house. Simply instruct ICM to change the TX and RX from the existing frequencies to the desired new frequencies. It'll cost you about $100 for the pair, but you'll wind up with crystals that are guaranteed to work on the new channels. 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 John D. Sent: Thursday, January 24, 2008 5:28 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] EF Johnson CR1010 Crystal Replacement I have a CR1010 repeater that needs to have new crystals installed to change the frequency from 451.200 to 451.250 on the TX and 456.200 to 456.250 on the Rx. I tried to get crystals from EF Johnson and they said they no longer support this repeater. I then tried to get crystals from International Crystal and they said there were two types of holders new and old. They said that if I had the new type I would be unable to get crystals for them or they would never work. It just so happens this repeater has the new crystals so does anybody know where I can get a set of old crystal holders so I can change the freq. on this repeater? Also does anybody have any other good ideas on how I can proceed with this unit. Thanks Ted Bleiman K9MDM MDM Radio If its in stock...we've got it! P O Box 31353 Chicago, IL 60631-0353 773.631.5130 fax 773.775.8096 web http://www.mdmradio.com - email - [EMAIL PROTECTED] DIRECT ALL EMAIL Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs
RE: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement
MDM, I was wondering about that myself! What does the New style elements look like? When were they installed by Johnson? I worked in a Johnson shop until 83 and still have a lot of Johnson radios on the air and don't remember anything like this. Admittedly, I have been out of the new Johnson equipment for a while. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Ted Bleiman K9MDM - MDM Radio Sent: Saturday, January 26, 2008 5:08 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement WONDERING OUT LOUD.WHO DID JOHNSON USE TO MAKE THEM IN THE FOIST PLACE??? MAYBE THEY CAN TELL YOU SINCE THEY OBVIOUSLY DIDN'T DO IT THEIR DAMN SELVES. SOME ONE HAD TO MFGR THE THINGS MDM --- Eric Lemmon [EMAIL PROTECTED] wrote: John, I stand corrected. I know that EFJ produced some oddball radios, but until now I have never heard of a crystal holder or channel element that could not be recrystalled by ICM. Live and learn! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of John D. Sent: Friday, January 25, 2008 5:55 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: EF Johnson CR1010 Crystal Replacement Eric, I tried that today and they positively will not work on the new type of crystal holders due to the way they are made since they cannot reliably make them work. They said they have done them in the past and lost money, wasted time, and angered customers in the process. John --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Eric Lemmon [EMAIL PROTECTED] wrote: John, I suggest that you send the holders, with the old crystals, to International Crystal or to any competent crystal house. Simply instruct ICM to change the TX and RX from the existing frequencies to the desired new frequencies. It'll cost you about $100 for the pair, but you'll wind up with crystals that are guaranteed to work on the new channels. 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 John D. Sent: Thursday, January 24, 2008 5:28 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] EF Johnson CR1010 Crystal Replacement I have a CR1010 repeater that needs to have new crystals installed to change the frequency from 451.200 to 451.250 on the TX and 456.200 to 456.250 on the Rx. I tried to get crystals from EF Johnson and they said they no longer support this repeater. I then tried to get crystals from International Crystal and they said there were two types of holders new and old. They said that if I had the new type I would be unable to get crystals for them or they would never work. It just so happens this repeater has the new crystals so does anybody know where I can get a set of old crystal holders so I can change the freq. on this repeater? Also does anybody have any other good ideas on how I can proceed with this unit. Thanks Ted Bleiman K9MDM MDM Radio If its in stock...we've got it! P O Box 31353 Chicago, IL 60631-0353 773.631.5130 fax 773.775.8096 web http://www.mdmradio.com - email - [EMAIL PROTECTED] DIRECT ALL EMAIL Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs Yahoo! Groups Links No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.11/1244 - Release Date: 1/25/2008 7:44 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.11/1244 - Release Date: 1/25/2008 7:44 PM Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] ICOM F221S Mobiles and Repeater
Seeking feedback on the ICOM F221S mobile or CY F221S repeater UHF versions as to suitability for use in the 70cm ham band. Can the radios be programmed with Windows software, or are they like many Motorola products - i.e., you need a slow computer running DOS. Thanks. Tony
RE: [Repeater-Builder] ICOM F221S Mobiles and Repeater
Tony, They are great little radios and you can program them with any Windows you want to. If you use them in repeater service turn the power down and use a good amp. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Tony L. Sent: Saturday, January 26, 2008 10:10 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] ICOM F221S Mobiles and Repeater Seeking feedback on the ICOM F221S mobile or CY F221S repeater UHF versions as to suitability for use in the 70cm ham band. Can the radios be programmed with Windows software, or are they like many Motorola products - i.e., you need a slow computer running DOS. Thanks. Tony Yahoo! Groups Links No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.12/1245 - Release Date: 1/26/2008 3:45 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.12/1245 - Release Date: 1/26/2008 3:45 PM Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
