Re: [Repeater-Builder] Desense, I'm guessing?
Eric Lemmon wrote: For those who may not have the Wacom catalog handy, the WP-643 duplexer comprises six 8 cavities that are rated at 102 dB isolation at 600 kHz spacing, with 2.2 dB insertion loss. Four of the cavities are BpBr, and two are bandpass only. The WP-639 duplexer comprises four 5 BpBr cavities that are rated at 80 dB isolation at 600 kHz spacing, with 1.5 dB insertion loss. Needless to say, the WP-643 is vastly superior to the WP-639 at 2m spacing. You could use two of the WP-639 cavities for bandpass application, if you replaced the single BpBr coupling loop with two Bp loops on each cavity. Try the WP-643 in stock form first. I totally agree with Eric's suggestions. Kevin Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
Kevin, Eric and all the WP-643's work great. And I dont even have the preamp installed and since i am happy with the performace with out the preamp and and the tx to rx range is about equal. It is locked Down and covers on. Thanks 6 8 cans are the way to go. - Original Message - From: Kevin Custer [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 22, 2005 5:26 AM Subject: Re: [Repeater-Builder] Desense, I'm guessing? Eric Lemmon wrote: For those who may not have the Wacom catalog handy, the WP-643 duplexer comprises six 8 cavities that are rated at 102 dB isolation at 600 kHz spacing, with 2.2 dB insertion loss. Four of the cavities are BpBr, and two are bandpass only. The WP-639 duplexer comprises four 5 BpBr cavities that are rated at 80 dB isolation at 600 kHz spacing, with 1.5 dB insertion loss. Needless to say, the WP-643 is vastly superior to the WP-639 at 2m spacing. You could use two of the WP-639 cavities for bandpass application, if you replaced the single BpBr coupling loop with two Bp loops on each cavity. Try the WP-643 in stock form first. I totally agree with Eric's suggestions. Kevin Yahoo! Groups Links --- [This E-mail scanned for viruses at TNWEB LLC] -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 --- [This E-mail scanned for viruses at TNWEB LLC] Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
Brent, Although there are those who will disagree with me on this, I think your WP-639 duplexer is simply not capable of sufficiently isolating your receive and transmit frequencies. While the WP-639 may get by on a low-powered system without a preamp, you may be demanding too much in your installation. Since the operating range of a repeater is limited more by its receive capability than by its power output, it makes sense to maximize the receive capability and run the minimum output power needed. First of all, the phrase factory tuned needs to be qualified. I will readily acknowledge that the majority of big-name duplexer manufacturers have the equipment (network analyzer) and expertise (highly-trained technicians) to properly tune a duplexer exactly to your stated operating frequencies. Very often, a factory-tuned duplexer is accompanied by a rather pompous statement of the form, This duplexer has been carefully tuned on laboratory-grade equipment, and NO FURTHER TUNING IS REQUIRED. Yeah, right! Unless I drove to the plant and picked up that duplexer myself, I can guarantee that it will be jostled, dropped, and bounced around during shipment to the point that it MAY be detuned enough to adversely affect its operation. I always check duplexers, isolators, and cavity filters on my own laboratory-grade equipment before installation, and I find perhaps 30% of them needing realignment. Please understand that the detuning most likely occurred during shipment, and is not the fault of the manufacturer. Whenever you put a preamp in front of a receiver, you really should put a very narrow bandpass cavity filter in front of it. It always comes as a surprise to neophyte repeater owners that a bandpass/bandreject or BpBr duplexer has almost no bandpass action at all. The notch or reject action is the major player, and the bandpass effect is minimal if nonexistent. Moreover, nearby carriers can sail right through the duplexer and cause major desense to your receiver. When you add a preamp, you are not just opening the barn door wider, you are amplifying all of the intruders! My personal preference is for two 8 bandpass cavities set for a total of 1.0 dB insertion loss after the receive side of the duplexer, and before the RF preamplifier. Don't be tempted to use one 10 or one 8 cavity set for 1.0 dB instead of two set for 0.5 dB each; the out-of-band rejection by two cavities is much greater than one cavity by itself. This is something I learned by experience- you can believe me now, or go off and find out for yourself. Trust me, you WILL settle on a minimum of two cavities. In the present climate of terrorist activity and natural disasters, it does not make any sense to deploy a repeater system that barely gets by or is good enough for the majority of users. It makes me very proud to be a member of an Amateur Radio group that designs and installs repeater systems that are as good as, and in many cases are better and more reliable than, commercial systems operated by public safety organizations. I sincerely wish that all repeater operators felt the same way! 73, Eric Lemmon WB6FLY Brent wrote: One of my 2m repeaters has a problem. It is a GE Mastr II base/repeater. I have a set of Wacom WP-639 on the machine, and an ARR preamp. ..a user 2 air miles from the site is wiped out of the receiver while the Tx is On, I turn the PA down below 20watts and he ( or all users) are clear. I have tried two different antennas before thinking about the duplexers, and want to double check other options before the cans.. these were factory tuned..cans. Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
With yours and Kevins reply, I have decided to go with a set of WP-643's and not use the WP-639's, I belive this would get me going. and if I need the pre amp then i will add it along with the pass cavities. One more Quick Question, since i have the set of 639's here. what would the affect of two cans from the 639s be if added to the 643's receiver side beside the loss. Brent - Original Message - From: Eric Lemmon [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 21, 2005 9:01 PM Subject: Re: [Repeater-Builder] Desense, I'm guessing? Brent, Although there are those who will disagree with me on this, I think your WP-639 duplexer is simply not capable of sufficiently isolating your receive and transmit frequencies. While the WP-639 may get by on a low-powered system without a preamp, you may be demanding too much in your installation. Since the operating range of a repeater is limited more by its receive capability than by its power output, it makes sense to maximize the receive capability and run the minimum output power needed. First of all, the phrase factory tuned needs to be qualified. I will readily acknowledge that the majority of big-name duplexer manufacturers have the equipment (network analyzer) and expertise (highly-trained technicians) to properly tune a duplexer exactly to your stated operating frequencies. Very often, a factory-tuned duplexer is accompanied by a rather pompous statement of the form, This duplexer has been carefully tuned on laboratory-grade equipment, and NO FURTHER TUNING IS REQUIRED. Yeah, right! Unless I drove to the plant and picked up that duplexer myself, I can guarantee that it will be jostled, dropped, and bounced around during shipment to the point that it MAY be detuned enough to adversely affect its operation. I always check duplexers, isolators, and cavity filters on my own laboratory-grade equipment before installation, and I find perhaps 30% of them needing realignment. Please understand that the detuning most likely occurred during shipment, and is not the fault of the manufacturer. Whenever you put a preamp in front of a receiver, you really should put a very narrow bandpass cavity filter in front of it. It always comes as a surprise to neophyte repeater owners that a bandpass/bandreject or BpBr duplexer has almost no bandpass action at all. The notch or reject action is the major player, and the bandpass effect is minimal if nonexistent. Moreover, nearby carriers can sail right through the duplexer and cause major desense to your receiver. When you add a preamp, you are not just opening the barn door wider, you are amplifying all of the intruders! My personal preference is for two 8 bandpass cavities set for a total of 1.0 dB insertion loss after the receive side of the duplexer, and before the RF preamplifier. Don't be tempted to use one 10 or one 8 cavity set for 1.0 dB instead of two set for 0.5 dB each; the out-of-band rejection by two cavities is much greater than one cavity by itself. This is something I learned by experience- you can believe me now, or go off and find out for yourself. Trust me, you WILL settle on a minimum of two cavities. In the present climate of terrorist activity and natural disasters, it does not make any sense to deploy a repeater system that barely gets by or is good enough for the majority of users. It makes me very proud to be a member of an Amateur Radio group that designs and installs repeater systems that are as good as, and in many cases are better and more reliable than, commercial systems operated by public safety organizations. I sincerely wish that all repeater operators felt the same way! 73, Eric Lemmon WB6FLY Brent wrote: One of my 2m repeaters has a problem. It is a GE Mastr II base/repeater. I have a set of Wacom WP-639 on the machine, and an ARR preamp. ..a user 2 air miles from the site is wiped out of the receiver while the Tx is On, I turn the PA down below 20watts and he ( or all users) are clear. I have tried two different antennas before thinking about the duplexers, and want to double check other options before the cans.. these were factory tuned..cans. Yahoo! Groups Links --- [This E-mail scanned for viruses at TNWEB LLC] -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 --- [This E-mail scanned for viruses at TNWEB LLC] Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
For those who may not have the Wacom catalog handy, the WP-643 duplexer comprises six 8 cavities that are rated at 102 dB isolation at 600 kHz spacing, with 2.2 dB insertion loss. Four of the cavities are BpBr, and two are bandpass only. The WP-639 duplexer comprises four 5 BpBr cavities that are rated at 80 dB isolation at 600 kHz spacing, with 1.5 dB insertion loss. Needless to say, the WP-643 is vastly superior to the WP-639 at 2m spacing. You could use two of the WP-639 cavities for bandpass application, if you replaced the single BpBr coupling loop with two Bp loops on each cavity. Try the WP-643 in stock form first. 73, Eric Lemmon WB6FLY Brent wrote: With yours and Kevin's reply, I have decided to go with a set of WP-643s and not use the WP-639s. I believe this would get me going, and if I need the pre-amp, then I will add it along with the pass cavities. One more quick question: Since I have the set of 639s here, what would the effect of two cans from the 639s be if added to the 643's receiver side- besides the loss? Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
Will do! Gone with just the Wp-643's nothing else. Thanks again for the info and of course the RPTIP info. which if I read or not I tend to always miss what im looking for. 73's Brent - Original Message - From: Eric Lemmon [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 21, 2005 9:59 PM Subject: Re: [Repeater-Builder] Desense, I'm guessing? For those who may not have the Wacom catalog handy, the WP-643 duplexer comprises six 8 cavities that are rated at 102 dB isolation at 600 kHz spacing, with 2.2 dB insertion loss. Four of the cavities are BpBr, and two are bandpass only. The WP-639 duplexer comprises four 5 BpBr cavities that are rated at 80 dB isolation at 600 kHz spacing, with 1.5 dB insertion loss. Needless to say, the WP-643 is vastly superior to the WP-639 at 2m spacing. You could use two of the WP-639 cavities for bandpass application, if you replaced the single BpBr coupling loop with two Bp loops on each cavity. Try the WP-643 in stock form first. 73, Eric Lemmon WB6FLY Brent wrote: With yours and Kevin's reply, I have decided to go with a set of WP-643s and not use the WP-639s. I believe this would get me going, and if I need the pre-amp, then I will add it along with the pass cavities. One more quick question: Since I have the set of 639s here, what would the effect of two cans from the 639s be if added to the 643's receiver side- besides the loss? Yahoo! Groups Links --- [This E-mail scanned for viruses at TNWEB LLC] -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 --- [This E-mail scanned for viruses at TNWEB LLC] Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
My experience so far is that the ARR preamps are terrible, very poor ability to not oscillate or overload when around any high RF field, we use only TXRX amps. So far, threw out 4 of the UHF ARR amps they make that were on repeaters. Even 100db pass/rej. duplexers don't seem to allow the amps to work correctly. lance N2HBA - Original Message - From: Brent [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 21, 2005 11:04 PM Subject: Re: [Repeater-Builder] Desense, I'm guessing? Will do! Gone with just the Wp-643's nothing else. Thanks again for the info and of course the RPTIP info. which if I read or not I tend to always miss what im looking for. 73's Brent - Original Message - From: Eric Lemmon [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, March 21, 2005 9:59 PM Subject: Re: [Repeater-Builder] Desense, I'm guessing? For those who may not have the Wacom catalog handy, the WP-643 duplexer comprises six 8 cavities that are rated at 102 dB isolation at 600 kHz spacing, with 2.2 dB insertion loss. Four of the cavities are BpBr, and two are bandpass only. The WP-639 duplexer comprises four 5 BpBr cavities that are rated at 80 dB isolation at 600 kHz spacing, with 1.5 dB insertion loss. Needless to say, the WP-643 is vastly superior to the WP-639 at 2m spacing. You could use two of the WP-639 cavities for bandpass application, if you replaced the single BpBr coupling loop with two Bp loops on each cavity. Try the WP-643 in stock form first. 73, Eric Lemmon WB6FLY Brent wrote: With yours and Kevin's reply, I have decided to go with a set of WP-643s and not use the WP-639s. I believe this would get me going, and if I need the pre-amp, then I will add it along with the pass cavities. One more quick question: Since I have the set of 639s here, what would the effect of two cans from the 639s be if added to the 643's receiver side- besides the loss? Yahoo! Groups Links --- [This E-mail scanned for viruses at TNWEB LLC] -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/2005 --- [This E-mail scanned for viruses at TNWEB LLC] Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
Re: [Repeater-Builder] Desense, I'm guessing?
At 11:28 PM 3/21/2005 -0500, you wrote: My experience so far is that the ARR preamps are terrible, very poor ability to not oscillate or overload when around any high RF field, we use only TXRX amps. So far, threw out 4 of the UHF ARR amps they make that were on repeaters. Even 100db pass/rej. duplexers don't seem to allow the amps to work correctly. --- I swear by AngleLinear preamps in all my receiver needs. No one else even comes close to Chip's equipment... Ken -- President and CTO - Arcom Communications Makers of state-of-the-art repeater controllers and accessories. http://www.ah6le.net/arcom/index.html We now offer complete Kenwood TKR repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * 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/
