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Cluster Activity

Spots per uW band today:
UK spotter or spotted only.

Solar data:
SFI
74
A-Index
11
K-Index
4
Exp.K
3
Sunspots
0
Activity
qui
GMF
act
Aurora?
no

My Weather

Date:21/11/17 Time:11:45
Temp:13C
Wind Speed:17.5mph
Wind Dir:202deg
Pressure:1002.75mB
Humidity:118%
Dew Point:16.6C
UKHASnet
13cm 200mW Comtech info

Watch out with you DC Power connections to the 200mW module!

The module requires a negative bias to the GAasFets in the final stages and this is done by using a virtual ground in the module.

All of the module Ground is held ~1.4v above DC Ground using the two diodes situated next to the tx can

This was only found by accident when in use on GB3KM where the dc ground was shorted to RF ground via the Power supply connections and eventually the Driver GAasFet failed!

A separate ground isolated power supply is required for the TX module at all times!!


200mW DC input

200mW top



200mW Module 6MHz Sound carrier boost:
200mW Module Sound boost











Last page added:16/08/17 15:45
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