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
