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- Subject: Modifying the Azden PCS-4000
- From: dave@eram.esi.com.au (Dave Horsfall)
-
- Modifying the Azden PCS-4000
-
- The Azden PCS-4000, popular some years ago, is a 25W mobile FM
- transceiver. Functions such as frequency selection etc are performed
- by a matrix of buttons on the front panel (and auxiliary buttons
- on the microphone); there is no "VFO" control as such. The control
- microprocessor continually scans this matrix; this scanning also
- applies to the frequency display and other functions.
-
- Many preset functions, such as band limits and step, are also under
- the control of the matrix, and these are readily modifiable by the
- user. NB: it is likely that other adjustments may have to be done
- if the band edges are changed.
-
- Call the scan lines K0 - K3 and R0 - R6 (using Azden's nomenclature);
- refer to the circuit diagram for their location. Lines K0-K3 take
- part in most operations, R0-R3 scan the keyboard, R4 scans the
- "M-Mode" switch, R5 selects the step, and R6 the band edge. The
- following are under control of these lines:
-
- [ O - Open, S - Short (diode) ]
-
- STEP
- R5
- 5K 10K 12.5K 15K 20K 25K 40K 50K
-
- K3 O O O O S S S S
-
- K2 O O S S O O S S
-
- K1 O S O S O S O S
-
- By default, the rig is shipped (in Australia anyway) with steps of
- 5 and 10 KHz; to change to 5 and 25 KHz it can be seen that all
- that is required is the addition of a diode at K3/R5. This can be
- done anywhere, but I installed mine on the small PCB holding the
- STEP switch behind the front panel; I prefer my mods to look as
- though they were original.
-
-
- BAND (2m version only)
-
- R6
- US JP EU
- US: 142.000 - 149.995, 5 kHz
- K3 O O O
- JP: 144.000 - 145.995, 5 kHz
- K2 O O S
- EU: 144.000 - 145.995, 12.5 kHz
- K1 O S O
-
- This is of limited use, unless you were contemplating modifying
- an imported set, in which case a realignment is probably necessary.
-
- --
- Dave Horsfall (VK2KFU) | dave@esi.com.au | VK2KFU @ VK2AAB.NSW.AUS.OC | PGP 2.6
- Opinions expressed are mine. | E7 FE 97 88 E5 02 3C AE 9C 8C 54 5B 9A D4 A0 CD
-