Yaesu FT290R for 9k6 Packet


FT790RI and FT290RI


Rx NF 1k2, 2k4 extraction on C 10 uF and 25 Kohm trimmer potentiometer (wiper outward) at collector of Q1021;
PTT on the side of extra jack, coupling via protection diode;
Rx NF 9k6 also decouple to pin 9 of the MC3357 Q1019;
NF Tx 9k6 (1k2, 2k4): rebuilding of Hubreglers VR02 so, grinders and "hot" end are reversed (right of the Q2004), coupling the signal to additional amplifiers on the grinder:
                               +——3,9K——-< + 5 Volt bis 6,8 Volt
                              |
                        +—–+—–22nF———+
                        |     |                  |
9k6                   220K    |                 22K
NF in                   |     C                  |
>—–+     +–0,47µF—+—–B 2SC945           +——–> NF out
      | TrPo|           |     E (BC109) o.ä.     |
     10K +–+           |     |                  |
      |               100K  330 Ohm            330K
    Masse               |     |                  |
                     Masse Masse              Masse




 TRPO = trimpot

Extraction also possible via 25 K trimpot, then grinding against amplifier, "hot" end to the outside;



Amplifier for 1k2, 2k4 Tx signal available;
when using a XR2211 - see above

Inexperienced, handcrafted should u.U. the fingers of the changes in FT290RI just leave!
73 de dg3oo @ db0cel-7. Nds.deu.eu # *** *** manfred
GW1NGL NA7KR Kevin Roberts Ham Radio
GW1NGL NA7KR Kevin Roberts Ham Radio

Page last updated on 09/10/2012 by Kevin Roberts NA7KR a colection of Ham Radio and Electronic Information