Topband: Waller Flag Question

[Andrew Ikin]

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