RE: [Repeater-Builder] Pair of GM300 as a repeater
In response to your Gm300s as repeaters, I have been using them for years without any problems, power up full(with fan coming on at transmit) and a 600 KHz spacing. I also have a pair of SM 50s working as a repeater with a much wider spacing. It has been operating for years now, without any problems. I will be happy to share more info. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Steve Sent: Friday, February 26, 2010 3:01 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Pair of GM300 as a repeater Hi they work OK but you must turn the tx pwr right down and fit a fan or pa won't last long. It is down to the duplexer finding a unit suitable at the right price will be almost impossible, the 5Mhz split is ok as you can get cheap duplexers from Hong Kong 73 Steve - Original Message - From: la88y llhorl...@gmail.com mailto:llhorlick%40gmail.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Thursday, February 25, 2010 4:46 PM Subject: [Repeater-Builder] Pair of GM300 as a repeater I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is the suggested minimum? Same questions for UHF SM50, but with a 5 mHz split? lh Yahoo! Groups Links
Re: [Repeater-Builder] Pair of GM300 as a repeater
Hi yes they do work, not intended for use as a repeater, even with a fan running full pwr is risky, depends on what sort of rptr if amateur then some of the overs can and do last 10 minutes or more. Again if amateur with a 600Kc split the dupexer will cost you a load of money Steve - Original Message - From: Leroy A. M. Baptiste leroybapti...@spiceisle.com To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 25, 2010 7:24 AM Subject: RE: [Repeater-Builder] Pair of GM300 as a repeater In response to your Gm300s as repeaters, I have been using them for years without any problems, power up full(with fan coming on at transmit) and a 600 KHz spacing. I also have a pair of SM 50s working as a repeater with a much wider spacing. It has been operating for years now, without any problems. I will be happy to share more info. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Steve Sent: Friday, February 26, 2010 3:01 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Pair of GM300 as a repeater Hi they work OK but you must turn the tx pwr right down and fit a fan or pa won't last long. It is down to the duplexer finding a unit suitable at the right price will be almost impossible, the 5Mhz split is ok as you can get cheap duplexers from Hong Kong 73 Steve - Original Message - From: la88y llhorl...@gmail.com mailto:llhorlick%40gmail.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Thursday, February 25, 2010 4:46 PM Subject: [Repeater-Builder] Pair of GM300 as a repeater I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is the suggested minimum? Same questions for UHF SM50, but with a 5 mHz split? lh Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Pair of GM300 as a repeater
Steve, So the reason for turning down the power is for PA protection or RF suppression? lh On Thu, Feb 25, 2010 at 2:00 PM, Steve steve.m1...@tiscali.co.uk wrote: Hi they work OK but you must turn the tx pwr right down and fit a fan or pa won't last long. It is down to the duplexer finding a unit suitable at the right price will be almost impossible, the 5Mhz split is ok as you can get cheap duplexers from Hong Kong 73 Steve - Original Message - From: la88y llhorl...@gmail.com llhorlick%40gmail.com To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Sent: Thursday, February 25, 2010 4:46 PM Subject: [Repeater-Builder] Pair of GM300 as a repeater I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is the suggested minimum? Same questions for UHF SM50, but with a 5 mHz split? lh Yahoo! Groups Links
Re: [Repeater-Builder] Pair of GM300 as a repeater
Hi they work OK but you must turn the tx pwr right down and fit a fan or pa won't last long. It is down to the duplexer finding a unit suitable at the right price will be almost impossible, the 5Mhz split is ok as you can get cheap duplexers from Hong Kong 73 Steve - Original Message - From: la88y llhorl...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 25, 2010 4:46 PM Subject: [Repeater-Builder] Pair of GM300 as a repeater I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is the suggested minimum? Same questions for UHF SM50, but with a 5 mHz split? lh Yahoo! Groups Links
Re: [Repeater-Builder] Pair of GM300 as a repeater
At 11:23 AM 02/25/10, you wrote: Steve, So the reason for turning down the power is for PA protection or RF suppression? lh PA protection. One caution (from the Introductory Information about the MaxTrac, Radius, GM300, etc radios page at repeater-builder... Remember that the MaxTrac, M-series, Radius and GM300 are MOBILE radios, made with minimal heat sinks, and while they can be used quite readily as a low-to-medium performance repeater receiver, or as a link receiver, you can NOT use it as a repeater transmitter or as a link transmitter without due consideration to the normal mobile radio limitations on RF power and duty cycle. ...and As a 10% to 15% duty cycle radio the MaxTrac, Radius and GM300 are designed to transmit for no more than 10 to 15 seconds out of each 100 seconds. ...and... It's one thing to use a GR300 (or similar) in a shopping mall environment to talk to the rent a cops or to tell housekeeping to clean up little Johnny's spilled ice cream cone, but you want something with a higher duty cycle as your primary repeater. By the way... I've seen a pair of the radios used as a repeater and there was more desense due to the cabling that came with the Moto duplexer kit (the RF cables from the radios to the duplexer) than due to radio case leakage. Once the cheap loose-weave braid cabling was replaced with the good stuff (RG400 and good connectors) all the measurable desense went away. Mike WA6ILQ
Re: [Repeater-Builder] Pair of GM300 as a repeater
On 2/25/2010 1:16 PM, Mike Morris WA6ILQ wrote: As a 10% to 15% duty cycle radio the MaxTrac, Radius and GM300 are designed to transmit for no more than 10 to 15 seconds out of each 100 seconds. Re: Duty-cycle. Is that really the engineering specification for duty-cycle, is it really in seconds/100? The reason I ask is I've always chuckled at duty-cycles presented as percentages. But it only transmitted 15 days straight, out of 100 days! Anyone know what the EIA/TIA duty-cycle tests for 100% duty cycle that many repeaters meet, REALLY tests for? Nate
Re: [Repeater-Builder] Pair of GM300 as a repeater
Hi someone answered this but mainly for PA protection as most mobiles are made for limited tx time. I made a UHF rptr with 2 GM300,s and an ICS controller, but I turned down the pwr to just 3 watts and fed it into a 6dB gain ant so erp is around 12w works well and gives the coverage I need. I will fit a better fan when I get time. Being in the UK we are only allows 25w erp so with a good ant no need to set tx pwr high. I also built a 6mtr rptr using 2 low band maxtracs and did the manual pwr mod to the tx unit, all great fun Steve - Original Message - From: Larry Horlick To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 25, 2010 7:23 PM Subject: Re: [Repeater-Builder] Pair of GM300 as a repeater Steve, So the reason for turning down the power is for PA protection or RF suppression? lh On Thu, Feb 25, 2010 at 2:00 PM, Steve steve.m1...@tiscali.co.uk wrote: Hi they work OK but you must turn the tx pwr right down and fit a fan or pa won't last long. It is down to the duplexer finding a unit suitable at the right price will be almost impossible, the 5Mhz split is ok as you can get cheap duplexers from Hong Kong 73 Steve - Original Message - From: la88y llhorl...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 25, 2010 4:46 PM Subject: [Repeater-Builder] Pair of GM300 as a repeater I'm wondering about the suitability of a pair of VHF GM300s as a repeater. Is the shielding sufficient to allow 600 kHz between Rx and Tx? If not, what is the suggested minimum? Same questions for UHF SM50, but with a 5 mHz split? lh Yahoo! Groups Links
Re: [Repeater-Builder] Pair of GM300 as a repeater
Hello Leroy, How did you program the radios? In other words, using the software how did you set up the Radiowide and Mode options in each radio. Specifically the Options settings. 73, Joe, K1ike Leroy A. M. Baptiste wrote: . I will be happy to share more info.
