TLD5803B EXCITER CONVERSION TO 220 MHZ BAND  

As of 7/30/05 this is good to go. Depending on the desired output you may need to change R436 to a different value.

Conversion done by wd7f, kd7txo (their brains) & k7iou (my brawn) 

C444 Was 18 pF   Now 5 pF silver mica

C448 Was 24 pF   Now 7.5 pF NPO disk

C449 Was 43 pF   Now 15 pF NPO disk

C453 Was 18 pF   Now 7.5 pF NPO disk

C452 Was 11 pF   Now 4.7 pF NPO disk

C456 Was 8 pF     Now 3.9 pF NPO disk

C457 Was 10 pF   Now 3.9 pF NPO disk

R434 Was 1.2k      Now 820 ohm

R435 Was 39 ohm Now 100 ohm

R436 Was 15 ohm Now 180 ohm. Change value to lower MW to desired output with the filter installed. This change gave us 110 MW drive for both our modules.  Also adjust the exciter pass filter for harmonic rejection. This filter will have some loss. 

Q406 Was M9390 Now 2N2222Z metal transistor. We changed this as our MW would start cold at 180 MW when keyed and drop to 114 MW on warm up. With this replacement it went to 300 Mw with the above value changes on the capacitors and resistors.

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Page recreated by: David Stanford k7iou Copyright 7/01/2005 B.A.R.T. and k7iou