Ramsey Electronics FX-440 Manual page 99

capacitor with s-h-o-r-t leads worked well. In later assembly, you'll
work with chip capacitors (and learn why they have machines
instead of people to put them in!).
( ] [ ] F3. Install R20, 100 ohms, upright (brown-black-brown).
( ] [ ] F4. Install R23, 100 ohms, upright (brown-black-brown).
[ ] [ ] FS. Recent improvements in the design of the FX-440 involve
changing the VCO buffer amp. We've replaced the transistor
stage, as with an MMIC (Microwave Monolythic Integrated
Circiut). This MMIC provides 13 dB of gain, 50 ohms input and
output inpedance, and flat frequency response. A part of this
nature was unheard of a few short years ago, and duplicates the
function of a small handful of components! Fitting this part on the
existing PC board requires careful following of the instructions.
I I I
] F6. Locate A1, the MSA0304 in its blister pack. Look carefully at
its body, you' II see a small molded dot near one lead. Refer to the
following drawing and GENTLY bend the lead with the dot and the
lead directly opposite. ·
BEND
LEAD~
BEND LEAD
'\.
.
/
DOT
R
[ ] [ ] F7. Install A 1, insert the two bent leads into the holes on the PC
designated as and solder.
~o::~
OBSERVE
POSITION
OF DOT I
~
[ ] [ ] F7a You will now have two remaining leads sticking out from
A 1 's body. Gently bend these leads down to the circuit board's
surface and solder.
[ ] [ ] F8. Install R115, 1 K, (brown-black-red).
[ ] [ ] F9. Install C46 and CSO, both 100 pf.
[ I [ I
F10. Install C38 and C57, both .001 uf.
[ I [ I
F11. Install C32, 100 pf.
[ ) [ ) F12. Install a16, 2SC2570, orient the flat side as shown.
FX-440 Assm. 39