Larcan IPA Information
IPA1 - 2 x MRF 148
These transistors are rated @30W each. As designed by Larcan,
in Aural service, they are driven with 120mW for an output power
of 12W. In visual service, they are driven with 12mW for an output
power of 1.2W. The manual states to adjust the bias on these
devices to 300mA for aural (FM) and 600mA for visual (VSB), though
there are handwritten notes elsewhere that state it should be 600mA
for both.

IPA2 - 2 x MRG 151G
These transistors are rated @300W each. As designed by Larcan,
in Visual service, they are driven with 600mW for an output power
of 600W. These are not used for Aural service.


Transmitter Chain - Aural
Exciter (240mW) split two ways to (2 x IPA1)
IPA1 - 120mW in, 12W out split two way (2 x FPA)
FPA - 6W in, 600W out

Transmitter Chain - Visual
Exciter (24mW) split two ways to (2 x IPA1)
IPA1 - 12mW in, 1.2W out split two way (2 x FPA)
IPA2 - 600mW in, 60W out split six ways to FPA FPA - 10W in, 1000W out


Scanned Images of relevant schematics ( 1Mb )

IPA1 Photos



IPA2 Photos