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Kelly,
The amp normally used in the high power MTT4BT-40 is the Mitsubishi RA30H1317M. It has various versions, including the ...M-101 ( Metal case and ROHS certified) There is a tiny set of contacts near the power trimmer pot that can be solder-bridged to provide the higher gate Voltage the the higher power amplifiers require. Don't jumper those if you have the smaller amp...it would be bad.
As a general rule of thumb, I try to route low level signals away from the RF output of the non-QRP transmitters like the RTG. A lot of people used to wrap the GPS cable around the antenna coax cable, resulting in RF "swamping" of trackers due to common-mode RF intrusion. This is especially an issue when compromise cable, like the RG-174u used in our little magnet mount antenna. I think you will probaly get away with your switch location, but if you see a lot of constant resetting, that will be the likely culprit.?
If you see constant or occasional continuous resetting in the RTG, its usually due to high SWR, or RF swamping due to installation issues. ( Like putting the GPS right next to your antenna) It can also happen due to inadequate supply current, making the power amplifier the heart of a noisy relaxation oscillator. ( This can happen with pretty much any transmitter) Constant resetting is pretty obvious. The LED will continue to flash red and green and not stop. In the RTG, this won't hurt the amp, which is amazingly robust and tolerant, but it will transmit an intermittent, low power clicking on your operational channel.?
73,
Allen AF6OF
-----Original Message-----
From: Kelly via groups.io <kellykeeton@...> To: [email protected] Sent: Sat, Nov 12, 2022 4:25 pm Subject: Re: [TinyTrak] MicroTrak-MTT4B-mods? GitHub thank you valuable feedback as always! corrections made! and ha nice..
If you feel the need to improve it's thermal happiness, you can remove the screws holding down the amp and add a little heat-sink thermal paste. The PCB makes a pretty good heatsink.its not so much I feel... on inspection PCB had more heat soaking discoloration then I would expect from break-in, so that was why I felt any need to go down the path at all? let me know I can photo the underside if interested? if the break in overdrive test or whatever is the cause and, I agree im not key down here. I am likely looking for smoke where there is none. and I was concerned about this cooling fin .. my concern started with the RTG and the location I mounted the profile/bank switch I was concerned I should have 180degree mounted it on the case. and was also concerned I should not have added headers but rather put the wire leads directly to the PCB to prevent any Spurr-RF. so I was being fancy by adding this photo fishing for any concerns as I also share.. I wanted to dig out the Rf-monitor to check the RTG switch as well and figured I would also be checking this work.. noted this is a mess on the page :) I was going to just perforate the case alone and below the pcb-sync but I wanted to hold off on case mods till I figure out LCD plan. asking for a friend the part number on the other case-amp? ;) |
