Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss
What RF preamp : Mirage "B-5016 G"?
232 views
Skip to first unread message
Tedd Doda
May 3, 1999, 3:00:00 AM5/3/99
to
HI People:
I have a Mirage B-5016-G 2 meter amplifier that lost its
receive preamp. The active device looks like a MAR series
amplifier. Does anyone know what this thing is so I can
order a replacement?
Mirage has not replied to 3 faxes, and numerous e-mail :(
Oh, BTW, the relays are fine.
Tedd Doda, CET
packet va3sed@va3sed ******* Running FBB under Warp Ver4
e-mail ve3...@rac.ca** Running the IAK in Warp Ver4
[Team OS/2 in Canada]
If replying, please remove .nospam from return address.
Dan K Nelson
May 3, 1999, 3:00:00 AM5/3/99
to
My B3016 did the same thing. An MPS2222 cured the problem. There were
actually two of them in the unit, one appeared to be part of the RF sensing
circuit, but since I had it open it was easy to replace them both while I
was there. You can get these transistors at Radio Shack, they're less than
$1.00 apiece.
actually two of them in the unit, one appeared to be part of the RF sensing
circuit, but since I had it open it was easy to replace them both while I
was there. You can get these transistors at Radio Shack, they're less than
$1.00 apiece.
73 de KF6KNB
Tedd Doda wrote in message <372d2...@flint.sentex.net>...
Mark Brown
May 3, 1999, 3:00:00 AM5/3/99
to
Hi Tedd
The transistor is supposedly an mgf1302, you can get them
from downeast microwave. A simple mod that will help with
thw transistor life and it also brings the noise figure way
down (2 s units of noise the old way, no s meter change
preamp on or off now and it hears MUCH better) is to add a
200 ohm trimpot in the drain lead and adjust for about 3
volts bias instead of 5 volts which is what is there in
stock form. There is a resistor in the drain lead circuit
that can be lifted to add the trimpot (do NOT install it
directly at the drain lead, unpleasant things could result).
I have done this to both my 6 and 2 meter bricks with very
good results.
73
Mark
The transistor is supposedly an mgf1302, you can get them
from downeast microwave. A simple mod that will help with
thw transistor life and it also brings the noise figure way
down (2 s units of noise the old way, no s meter change
preamp on or off now and it hears MUCH better) is to add a
200 ohm trimpot in the drain lead and adjust for about 3
volts bias instead of 5 volts which is what is there in
stock form. There is a resistor in the drain lead circuit
that can be lifted to add the trimpot (do NOT install it
directly at the drain lead, unpleasant things could result).
I have done this to both my 6 and 2 meter bricks with very
good results.
73
Mark
0 new messages