Re: [Repeater-Builder] Noise Level on a Duplexer
Kent, I have seen this sort of problem before in a simaler application. I believe that your duplexer may have a bad internal connection, possibly at a fingerstock contact. In my case the problem was solved by replacing the duplexer. I believe the problem was caused by tuning the duplexer under power rather than with a network analyser. This occured many years ago, so my memory may be faulty. Best Regards de Eric (W1EL) Eric Lowell Eastern Maine Electronics Inc. 48 Loon Road Wesley ME 04686 eme@starband.net www.satnetmaine.com 207-210-7469 From: Kent Chong kentchon...@yahoo.com.sg To: Repeater-Builder@yahoogroups.com Sent: Tue, March 9, 2010 10:31:30 AM Subject: Re: [Repeater-Builder] Noise Level on a Duplexer Dear Joe, Yes, we have observed the signal with a spectrum analyser. It is a broadband noise covering our entire TETRA band. Yes, the transmitter is keyed up continually. Regarding oscillation, what circuitry will develop the oscillation in 3 days? We are thinking about the heat problem too, as heat may be developed overtime. Best Regards, Kent --- On Tue, 9/3/10, Joe k1ike_m...@snet. net wrote: From: Joe k1ike_m...@snet. net Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@ yahoogroups. com Date: Tuesday, 9 March, 2010, 8:52 PM Hello Kent, Have you looked at the noise on a spectrum analyzer? Is is broadbanded noise, or is it just on your receiver frequencies? If it is only on specific frequencies, is it frequency stable or does it drift around? Also, do any of your transmitters stay constantly keyed up? I'm wondering if something external to your system is oscillating. Your signals may be causing it to go into self-oscillation. When you shut your system off it stops. This is just a guess right now. 73, Joe, K1ike http://sg.rd. yahoo.com/ sg/mail/domainch oice/mail/ signature/ *http://mail. promotions. yahoo.com/ newdomains/ sg/ Get your new Email address! Grab the Email name you've always wanted before someone else does!
Re: [Repeater-Builder] Noise Level on a Duplexer
Dear Eric, Thank you for your mail. Yes, we found that the interconnect T-Join between two system is heated up. Could we just cool down the T-Join for there is other way to solve this issue? Best Regards, Kent --- On Wed, 10/3/10, Eric Lowell elowell9...@yahoo.com wrote: From: Eric Lowell elowell9...@yahoo.com Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@yahoogroups.com Date: Wednesday, 10 March, 2010, 8:54 PM Kent, I have seen this sort of problem before in a simaler application. I believe that your duplexer may have a bad internal connection, possibly at a fingerstock contact. In my case the problem was solved by replacing the duplexer. I believe the problem was caused by tuning the duplexer under power rather than with a network analyser. This occured many years ago, so my memory may be faulty. Best Regards de Eric (W1EL) Eric Lowell Eastern Maine Electronics Inc. 48 Loon Road Wesley ME 04686 eme@starband. net www.satnetmaine. com 207-210-7469 From: Kent Chong kentchongkm@ yahoo.com. sg To: Repeater-Builder@ yahoogroups. com Sent: Tue, March 9, 2010 10:31:30 AM Subject: Re: [Repeater-Builder] Noise Level on a Duplexer Dear Joe, Yes, we have observed the signal with a spectrum analyser. It is a broadband noise covering our entire TETRA band. Yes, the transmitter is keyed up continually. Regarding oscillation, what circuitry will develop the oscillation in 3 days? We are thinking about the heat problem too, as heat may be developed overtime. Best Regards, Kent --- On Tue, 9/3/10, Joe k1ike_m...@snet. net wrote: From: Joe k1ike_m...@snet. net Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@ yahoogroups. com Date: Tuesday, 9 March, 2010, 8:52 PM Hello Kent, Have you looked at the noise on a spectrum analyzer? Is is broadbanded noise, or is it just on your receiver frequencies? If it is only on specific frequencies, is it frequency stable or does it drift around? Also, do any of your transmitters stay constantly keyed up? I'm wondering if something external to your system is oscillating. Your signals may be causing it to go into self-oscillation. When you shut your system off it stops. This is just a guess right now. 73, Joe, K1ike http://sg.rd. yahoo.com/ sg/mail/domainch oice/mail/ signature/ *http://mail. promotions. yahoo.com/ newdomains/ sg/ Get your new Email address! Grab the Email name you've always wanted before someone else does! New Email names for you! Get the Email name you#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! http://mail.promotions.yahoo.com/newdomains/sg/
Re: [Repeater-Builder] Noise Level on a Duplexer
On Wed, 10 Mar 2010, Kent Chong wrote: Yes, we found that the interconnect T-Join between two system is heated up. Could we just cool down the T-Join for there is other way to solve this issue? Replace the tee. It has failed, or one of the connectors attached to the coax has failed and the heat is conducting into the tee. -- Kris Kirby, KE4AHR Disinformation Analyst
RE: [Repeater-Builder] Noise Level on a Duplexer
Hello Kent, Everybody go in the same trail but not at the same time Many year ago I have had a trouble and similar than yours, a Q202 duplexer refuse to work properly and my final approach was to replace all the N type T connectors by new one, good one, silver plated with real Mil spec and our problem disappear. Some T adaptor use a little spring in between the line to do contact on the center pin of the T, these type are so cheap and they are made by Provo. (Please, NEVER USE THAT KIND OF ... ) I hope this help you a little bit... 73 Eric VE2VXT / VE7YBC _ De : Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] De la part de Kent Chong Envoyé : 10 mars 2010 07:12 À : Repeater-Builder@yahoogroups.com Objet : Re: [Repeater-Builder] Noise Level on a Duplexer Dear Eric, Thank you for your mail. Yes, we found that the interconnect T-Join between two system is heated up. Could we just cool down the T-Join for there is other way to solve this issue? Best Regards, Kent --- On Wed, 10/3/10, Eric Lowell elowell9...@yahoo.com wrote: From: Eric Lowell elowell9...@yahoo.com Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@yahoogroups.com Date: Wednesday, 10 March, 2010, 8:54 PM Kent, I have seen this sort of problem before in a simaler application. I believe that your duplexer may have a bad internal connection, possibly at a fingerstock contact. In my case the problem was solved by replacing the duplexer. I believe the problem was caused by tuning the duplexer under power rather than with a network analyser. This occured many years ago, so my memory may be faulty. Best Regards de Eric (W1EL) Eric Lowell Eastern Maine Electronics Inc. 48 Loon Road Wesley ME 04686 eme@starband. net www.satnetmaine. com 207-210-7469 _ From: Kent Chong kentchongkm@ yahoo.com. sg To: Repeater-Builder@ yahoogroups. com Sent: Tue, March 9, 2010 10:31:30 AM Subject: Re: [Repeater-Builder] Noise Level on a Duplexer Dear Joe, Yes, we have observed the signal with a spectrum analyser. It is a broadband noise covering our entire TETRA band. Yes, the transmitter is keyed up continually. Regarding oscillation, what circuitry will develop the oscillation in 3 days? We are thinking about the heat problem too, as heat may be developed overtime. Best Regards, Kent --- On Tue, 9/3/10, Joe k1ike_m...@snet. net wrote: From: Joe k1ike_m...@snet. net Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@ yahoogroups. com Date: Tuesday, 9 March, 2010, 8:52 PM Hello Kent, Have you looked at the noise on a spectrum analyzer? Is is broadbanded noise, or is it just on your receiver frequencies? If it is only on specific frequencies, is it frequency stable or does it drift around? Also, do any of your transmitters stay constantly keyed up? I'm wondering if something external to your system is oscillating. Your signals may be causing it to go into self-oscillation. When you shut your system off it stops. This is just a guess right now. 73, Joe, K1ike http://sg.rd. yahoo.com/ sg/mail/domainch oice/mail/ http://sg.rd.yahoo.com/sg/mail/domainchoice/mail/signature/*http:/mail.prom otions.yahoo.com/newdomains/sg/ signature/ *http://mail. promotions. yahoo.com/ newdomains/ sg/ _ Get your new Email address! http://sg.rd.yahoo.com/sg/mail/domainchoice/mail/signature/*http:/mail.prom otions.yahoo.com/newdomains/sg/ Grab the Email name you've always wanted before someone else does! _ New http://sg.rd.yahoo.com/sg/mail/domainchoice/mail/signature/*http:/mail.prom otions.yahoo.com/newdomains/sg/ Email names for you! Get the Email name you've always wanted on the new @ymail and @rocketmail. Hurry before someone else does! __ Information from ESET NOD32 Antivirus, version of virus signature database 4932 (20100310) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __ Information from ESET NOD32 Antivirus, version of virus signature database 4932 (20100310) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com __ Information from ESET NOD32 Antivirus, version of virus signature database 4932 (20100310) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
Re: [Repeater-Builder] Noise Level on a Duplexer
Dear Joe, Yes, we have observed the signal with a spectrum analyser. It is a broadband noise covering our entire TETRA band. Yes, the transmitter is keyed up continually. Regarding oscillation, what circuitry will develop the oscillation in 3 days? We are thinking about the heat problem too, as heat may be developed overtime. Best Regards, Kent --- On Tue, 9/3/10, Joe k1ike_m...@snet.net wrote: From: Joe k1ike_m...@snet.net Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@yahoogroups.com Date: Tuesday, 9 March, 2010, 8:52 PM Hello Kent, Have you looked at the noise on a spectrum analyzer? Is is broadbanded noise, or is it just on your receiver frequencies? If it is only on specific frequencies, is it frequency stable or does it drift around? Also, do any of your transmitters stay constantly keyed up? I'm wondering if something external to your system is oscillating. Your signals may be causing it to go into self-oscillation. When you shut your system off it stops. This is just a guess right now. 73, Joe, K1ike http://sg.rd. yahoo.com/ sg/mail/domainch oice/mail/ signature/ *http://mail. promotions. yahoo.com/ newdomains/ sg/
Re: [Repeater-Builder] Noise Level on a Duplexer
Hello Kent, Have you looked at the noise on a spectrum analyzer? Is is broadbanded noise, or is it just on your receiver frequencies? If it is only on specific frequencies, is it frequency stable or does it drift around? Also, do any of your transmitters stay constantly keyed up? I'm wondering if something external to your system is oscillating. Your signals may be causing it to go into self-oscillation. When you shut your system off it stops. This is just a guess right now. 73, Joe, K1ike http://sg.rd.yahoo.com/sg/mail/domainchoice/mail/signature/*http://mail.promotions.yahoo.com/newdomains/sg/
[Repeater-Builder] Noise Level on a Duplexer
Hello Everybody, Good day. We have developed a Duplexer to combine to two signals form two systems for in-building application. The Dupluxer (or combiner) has specifications of 1.7dB insertion loss and 60dB isolation. When we set up the system and power on the two systems, the combiner works fine. However, we notice that the noise level (up link) on the two systems will slowly increase, and until 3~4 days later, the noise level has increased to -80~-60dBm level. We then power down the systems for 3 hours, and power them up again. The systems work fine again. Anybody could help? Best Regards, Kent New Email names for you! Get the Email name you#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! http://mail.promotions.yahoo.com/newdomains/sg/
Re: [Repeater-Builder] Noise Level on a Duplexer
What specific radios, and would 3 hours be enough for the radios themselves or any other components they might be heating to return to room-temperature (whatever that is where they're installed)? Nate WY0X On 3/8/2010 10:03 AM, Kent Chong wrote: Hello Everybody, Good day. We have developed a Duplexer to combine to two signals form two systems for in-building application. The Dupluxer (or combiner) has specifications of 1.7dB insertion loss and 60dB isolation. When we set up the system and power on the two systems, the combiner works fine. However, we notice that the noise level (up link) on the two systems will slowly increase, and until 3~4 days later, the noise level has increased to -80~-60dBm level. We then power down the systems for 3 hours, and power them up again. The systems work fine again. Anybody could help? Best Regards, Kent
Re: [Repeater-Builder] Noise Level on a Duplexer
What frequency are you on? Joe Kent Chong wrote: Hello Everybody, Good day. We have developed a Duplexer to combine to two signals form two systems for in-building application. The Dupluxer (or combiner) has specifications of 1.7dB insertion loss and 60dB isolation. When we set up the system and power on the two systems, the combiner works fine. However, we notice that the noise level (up link) on the two systems will slowly increase, and until 3~4 days later, the noise level has increased to -80~-60dBm level. We then power down the systems for 3 hours, and power them up again. The systems work fine again. Anybody could help? Best Regards, Kent New Email names for you! http://sg.rd.yahoo.com/sg/mail/domainchoice/mail/signature/*http://mail.promotions.yahoo.com/newdomains/sg/ Get the Email name you've always wanted on the new @ymail and @rocketmail. Hurry before someone else does!
Re: [Repeater-Builder] Noise Level on a Duplexer
Dear Joe, One system is on 380~400Mhz, and the other one is on 470~490Mhz. Best Regards, Kent --- On Tue, 9/3/10, Joe k1ike_m...@snet.net wrote: From: Joe k1ike_m...@snet.net Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@yahoogroups.com Date: Tuesday, 9 March, 2010, 7:29 AM What frequency are you on? Joe Kent Chong wrote: Hello Everybody, Good day. We have developed a Duplexer to combine to two signals form two systems for in-building application. The Dupluxer (or combiner) has specifications of 1.7dB insertion loss and 60dB isolation. When we set up the system and power on the two systems, the combiner works fine. However, we notice that the noise level (up link) on the two systems will slowly increase, and until 3~4 days later, the noise level has increased to -80~-60dBm level. We then power down the systems for 3 hours, and power them up again. The systems work fine again. Anybody could help? Best Regards, Kent - - - - - - New Email names for you! http://sg.rd. yahoo.com/ sg/mail/domainch oice/mail/ signature/ *http://mail. promotions. yahoo.com/ newdomains/ sg/ Get the Email name you've always wanted on the new @ymail and @rocketmail. Hurry before someone else does! New Email addresses available on Yahoo! Get the Email name you#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! http://mail.promotions.yahoo.com/newdomains/sg/
Re: [Repeater-Builder] Noise Level on a Duplexer
Dear Nate, They are TETRA TETRAPOL systems. It seems like our Duplexer that is causing the problem, as the TETRA system bypasses the Combiner, the noise is removed. At first, we were thinking it is the heat problem, but the system is installed in an air-condition room at 25 deg C, and the Duplexer is not heated up. Best Regards, Kent --- On Tue, 9/3/10, Nate Duehr n...@natetech.com wrote: From: Nate Duehr n...@natetech.com Subject: Re: [Repeater-Builder] Noise Level on a Duplexer To: Repeater-Builder@yahoogroups.com Date: Tuesday, 9 March, 2010, 6:08 AM What specific radios, and would 3 hours be enough for the radios themselves or any other components they might be heating to return to room-temperature (whatever that is where they're installed)? Nate WY0X On 3/8/2010 10:03 AM, Kent Chong wrote: Hello Everybody, Good day. We have developed a Duplexer to combine to two signals form two systems for in-building application. The Dupluxer (or combiner) has specifications of 1.7dB insertion loss and 60dB isolation. When we set up the system and power on the two systems, the combiner works fine. However, we notice that the noise level (up link) on the two systems will slowly increase, and until 3~4 days later, the noise level has increased to -80~-60dBm level. We then power down the systems for 3 hours, and power them up again. The systems work fine again. Anybody could help? Best Regards, Kent New Email addresses available on Yahoo! Get the Email name you#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! http://mail.promotions.yahoo.com/newdomains/sg/
