EME103 PREAMPLIFIER

EME103 13/23cm PREAMPLIFIER KIT
Thursday 5th June 08

KIT CONSTRUCTORS ALERT:
KIT CONSTRUCTION NOTES:
KIT FAULTS & MODIFICATIONS:
PROTOTYPE TESTS:

EME103 KIT CONSTRUCTORS ALERT

This applies to all Kits between January & June 2008. A number of constructors have reported that the voltages around the MGF1302 GasFET have been incorrect. Some have found the BC857 transistor to be faulty. We have in fact found that the complete batch of BC857 Transistors supplied to us in December were in fact 6.2 volt Zener diodes. The Transistor should have a 3H marking on the case. Please email us if you have the problem & we will post a replacement BC857 transistor to you.

KIT FAULTS & MODIFICATIONS

1/ This applies to all Kits between January & June 2008. A number of constructors have reported that the voltages around the MGF1302 GasFET have been incorrect. Some have found the BC857 transistor to be faulty. We have in fact found that the complete batch of BC857 Transistors supplied to us in December were in fact 6.2 volt Zener diodes. Please email us if you have the problem & we will post a replacement BC857 transistor to you.

2/ Any instability problems are usually caused by the RF connections in & out of the board. Connectors that are suitable are listed in the Kit notes. Boxes can also cause instability as they can act like Microwave Waveguides. Boxes that are close to a Waveguide size for 1200 to 2400MHz should be avoided.

BELOW SHOWS THE TESTED RESULTS OF THE PROTOTYPE KITS

We did this some time back & are looking for our test results.