Connecting the Daniels MT-2 VHF receiver module:

Input section: Four section helical filter, with bipolar transistor preamplifier.

Local oscillator: TCXO with two section helical filter, feeding the first IF at 21.4 MHz, and second IF at 455 kHz.

I got my crystals from West crystals:
West Crystal, 10-2550 Acland Rd Kelowna BC V1X 7L4
(250) 765-4833 Fax: (250) 765-3308
wcrystal@shaw.ca   http://www.westcrystal.com/index2.html
West Crystals no longer manufactures this product, and ICM has not been able to temp-comp the Daniels modules.

The crystals are carried in TCXO modules, a small green ice-cube like case, with gold pins, a single gold screw on the top, and an adjustment hole. If you don't have this module, you are in a bit of trouble. The actual oscillator is on the receiver board, but the module contains several thermistors, and a varactor, and will prove to be difficult to duplicate.

In terms of connections, this module is practically identical to the UHF receiver module, but I will present the connection data again, so that each document is complete on it's own.

This module only needs 9.5VDC to operate.

It provides a 0-5V received signal strength indicator (RSSI) output, a 3V nominal AFC output, and several options for audio output.

Squelch is internally adjustable. Squelch hysteresis can be externally disabled, and squelch can be turned off externally.

Audio outputs normally available are:
Discriminator (non de-emphasized)
De-emphasised audio, filtered, for CTCSS detection

Optional audio outputs:
5W speaker audio
600 ohm balanced audio (simple to install if you want to)

Control signals are all low true, so you ground KEY to transmit, and COR goes low to indicate presence of a signal.

All the input pins have EMI filter network. These networks consist of a series inductor and 330pF cap to ground.

The rear panel connector is a DIN standard connector, with three columns of even numbered pins, numbered from 1 to 32. The three columns are labeled on the connector, "D", "B", and "Z", at the top. The pins are numbered on the right side, but only the rightmost digit shows, so you see this:

D B Z O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

Row Number 2 4 6 8 0 (should be 10) 2 (should be 12) 4 (should be 14) 6 (should be 16) 8 (should be 18) 0 (should be 20) 2 (should be 22) 4 (should be 24) 6 (should be 26) 8 (should be 28) 0 (should be 30) 32

Receiver modules:
The "D" column is not connected. I would not say that it is safe to make connections to those pins though, just that the manual does not list any connections to them. "No connection" and "DONT CONNECT" aren't the same thing.

The receiver connections are as follows, from the VR-2 MT-2 manual.
The UHF receiver connections are the same.

Function	Pin(s)	Comment
Ground	B30, Z30, B32, Z32
+9.5V in	B6, Z6
B-System	B16,Z16	Jumper inside the RX connects this point with B6,Z6
6.0Vdc out	Z4
COR normal	B12,Z12	Goes to ground when signal present
COR Isolated	B16,Z16	Optional opto-isolated COR, + on B16, - on Z16
Squelch Hysteresis control	Z28	Ground to remove hysteresis
AFC voltage	Z24	Should be 3.0V for on-frequency input signal
CTCSS audio	B14	Disc output before any processing or squelch
Balanced audio	B26 to Z26	Optional 600 ohm balanced output, if you have this, you'll see a quarter-sized transformer on the PCB
Aux speaker audio	B4
De-Emphasized audio	B22
Flat audio	B20
Squelch override input	Z14	Ground to open the squelch
Carrier strength	B24	0-5 volts
Mute input	B28	Asserting this mute signal low will prevent the COR output from happening

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The information presented in and on these conversion pages is © Copyrighted 1995 - (date of last update) by Kevin Custer W3KKC and multiple originating authors.