Tom, It appears that the final transistor Q2740 is dead, and the driver transistor Q2730 is running wide open. The driver normally provides about 13 watts to the final. Check all solder joints and verify the correct DC voltages are present during transmit. An RF millivoltmeter can be a great help in troubleshooting this problem.
The complete MaxTrac service manual 6880102W84 is available for download on the RBTIP, and Part 4 of 4 covers the power amplifier. The 17.1 MB file is here: <www.repeater-builder.com/maxtrac/files/maxtrac-manual-6880102w84-o-4-of-4.p df> or as a TinyURL: <http://tinyurl.com/5qoar8> Let's hope that the final PA transistor is okay, because it (4880225C24) costs about $110 from Motorola. I did a cursory search on the Internet and found a supplier in Mexico selling the same part for about $65. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of tgundo2003 Sent: Friday, June 06, 2008 10:52 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Maxtrac Question I have a UHF (D44) 40w 449-470 maxtrac on the bench. All checks out good, except power out. Most I can get out of it is 22 watts, and that happens at 92 on the adjustment scale, any values above 92 yield no difference in power output. Here is the strange thing- I get more out (22W) at 441.300, and only 14w at 467.xxx. Since this is a 449-470 split I would think it would be the opposite. Anyone have any thoughts? Tom W9SRV
