At 12:59 PM 2/16/2011, Ted wrote: >I just sent my ARR pre amp back to ARR for repair for the 3rd time ! > >(pretty sure I did not tx through it ) > >What are people using for pre amps. I only see the Mirage as an alternative. >Any other choices. I'm kind of disappointed in ARR products. >Is there a pre amp that you can tx through preventing accidental frying? > >Any thoughts appreciated > >73, Ted, K7TRK >_______________________________________________ >Sent via [email protected]. Opinions expressed are those of the author. >Not an AMSAT-NA member? Join now to support the amateur satellite program! >Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Ted, Not without relays to bypass the preamp when transmitting. Several outfits make preamps with RF detect and internal relays but be careful not to exceed their RF power ratings. ARR make a fine preamp and I have used them for years. The mgf-1302 is the standard device in them but have become scarce (hard to find). Not sure what ARR is using as a substitute, but you could stock up on a handful and do your own repairs. I have been the beneficiary of a couple dozen H-J Fets (NE334S01) that drop into the ARR and have half the NF (typ. 0.24 dBNF). They are smaller devices so a bit harder to handle. I just installed one in an old P144VDG ARR preamp and had only to substitute the 100-ohm resistor with a 270-ohm to supply Vds=2.4v (mgf-1302 take Vds=4v). I will be installing it on my 2m-eme array in a couple days and will see how it plays. 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com EME: 144-1.4kw*, 432-100w, 1296-testing*, 3400-winter? DUBUS Magazine USA Rep [email protected] ====================================== *temp not in service _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
