Art Delibert wrote on Set. 6
snip <The on-line materials about Waller Flags says that a modest size WF
would need about 40 dB of gain to boost the signal to a usable level. One
of the postings says that cascading two preamps of 20 dB each seems to add
extra noise, and they talk about developmental work being done on a single
preamp of 40 dB.
Is there now such a 40 dB preamp? Is it made commercially? Alternatively,
are there plans on-line somewhere? Has someone actually used it in a
high-RF urban/suburban area, with multiple 50 kW AM BC stations? With what
results?>
Art, The Wellbrook FLG100LN Flag Head amplifier may offer a partial
solution to the gain and IMD issue with multiple 50kW AM Tx. The amp. has a
23dB gain and a near to zero NF. The current production has an OIP3 of
+49dBm and OIP2 of +90dBm. Additional 17dB gain in the shack could be
afforded with a Dxeng RPA-1.
Unfortunately, the Website details for the FLG100LN have not been updated to
reflect the new design. Basically the new FLG100LN is the ALA100LN Loop
amplifier with an 800 Ohm input matching/ Isolation transformer.
73
Andrew Ikin
G8LUG
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