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Yaesu FT7200 Mod - Call Tone 1750 Hz volume increase [message #139] Sun, 05 August 2007 00:14
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Registered: December 2004
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I'm a long time user of the Yaesu FT-7200. This transceiver came with a very low level 1750 Hz repeater tone.
Nearly no repeater could be opened easily, at least you hda to press the call button a very long time.

If you compare the volume/deviation of different transceivers you will 'hear' what I'm talking about.

I know that nowadays the repeaters should use a lower deviation, but this can be adjusted with a summing resistor R1058 on the main unit. See the picture attached.

Please be aware that this modifihoneyion also influences the level of the CTCSS sub-tones.Check the circuit diagram for details.

The recommendation to REPLACE R1058 I did not like, It might damage the PCB as the components are glued to the board. It's much easier to switch 68 kOhms in parallel, changing the value allows an adjustment of the deviation. (68k//68k=34k) Comparing the volume (and spectrum on a spectrum analyzer) I found out that 68 kOhms work fine.
Use a very small wired resistor or a SMD version and be sure that not short circuit occur.

Please proceed at your own risk.

Good luck! Wolfgang DH3WO

[Updated on: Sun, 05 August 2007 00:15]

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