rhaamo / bel-lhp-219

BEP LHP 219

Notes and various about this indian military radio.

Notes

All schematics are a "View From Top", like seeing in X-ray from the top. That was easier to reverse the PCBs.

Coil trimmers value is not known, markings on them are like "108 205", "108 201", etc.

Known values of caps might not be right, some have color code (top to bot: orange red red) or only military part number without a lookup table.

Unless determined by schematics, Test Points doesn't have indications on what they are.

Links

• Some specs: http://www.greenradio.de/htm2/e_lhp219.htm
• Full teardown: https://www.youtube.com/watch?v=M3-ErxbTwJw

H6 - Filter In

TP

J3: LSB Filter In
J4: GND
J5: CW Filter In
J6: RF in from pin3 (pin 3 of H14 connector, coax white/blue)
J7: 

H7 - Filter Out

TP

J3: LSB Filter Out
J4: GND
J5: CW Filter Out
J6: 
J7: 

H8 - A.G.C

H9A - Detector And Receive Audio

TP

J3: Audio Out (to front connectors)
J4: Audio In (from RX circuit through 108k gain pot)

H10 - 1750/1751KHz Generator

TP

J3: Emitter of Q3
J4:

H11 - Summing Amplifier And 10V Regulator

TP

J3:
J4:
J5:

H12 - Transmitter IF

TP

J3: Q1 in from IC2
J4: Q3 in from IC1

H13 - Transmit Audio And Tone Generator

TP

J3: 
J4: 

H14 - Hinged PCB Modules (H6, H7, H8, H9A, H10, H11, H12, H13, Crystal Filters: CW and LSB)

H25A - Voltage Regulator +18V +14V

Pins

1: +18V (TP J2)
4: +14V (TP J3)
7: In
10: GND

H27 - Synthesizer assembly (H15, H16, H18, H20, H24-Y1, H21, H22, H25, H26)

H21 - Phase Comparator

H5 - Tuned Amplifier Assembly

H5-4

H5-3

H5-2

H5-1

Rotary selector and filters connection

Connectors

H14 - Hinged PCB Connector

Front panel (except frequency selectors)

Block diagrams

HF

Battery

24V.

A -
B +
C N/C

Front power connector

Untested.

+ goes to battery +, minus..., ? are unknown.

+ -
 ? ?
? -

Headsets

H189 or H250 might works, connector is a U-183/U, corresponding headset connector is U-182B/U, U-229/U.

All modules

Synthesizer, N 43547, H27

Name	"Schematized"	Reference 1	Reference 2
Tuned Amplifier	Yes	N 43586	H5
Coil Block	No	N 43553	H15
Voltage Controlled Oscillator	Not Yet	N 43929	H16A
5 Bit D/A Converter And Summing & Buffer Amplifier	Not Yet	N 43847	H18
Programmable Divider	No	1000 043 538 40	H20
Phase Comparator	Yes	N 43537	H21
Frequency Detector And Standard Divider	Not Yet	N 43848	H22
BULOVA TXCO-1 FREQ 3.5MHz	N/a	A410181	H24
Voltage Regulator +18V +14V	Yes	1140 001 980 78	H25A
Switching Regulator 5V	No	N 43531	H26

Main

Name	"Schematized"	Reference 1	Reference 2
Power Supply	No	N 43680	H1
Driver	No	N 43685	H2
Aerial Filter, ALC & Metering Unit	No	N 43655	H3

Hinged Module Assembly, H14

Name	"Schematized"	Reference 1	Reference 2
Filter In	Yes	N 43706	H6
Filter Out	Yes	N 43707	H7
A.G.C	Yes	N 43708	H8
Detector And Receive Audio	Yes	1140 006 871 52	H9A
1750/1751KHz Generator	Yes	N 43710	H10
Summing Amplifier And 10V Regulator	Yes	N 43711	H11
Transmitter IF	Yes	N 43712	H12
Transmit Audio And Tone Generator	Yes	N 43713	H13
Crystal Filter CW Freq 1.75MHz	N/a
Crystal Filter LSB Freq 1.75MHz	N/a

Front

Name	"Schematized"	Reference 1	Reference 2
Power Amp	No	N 43668	H4

Various notes

Audio path (WIP):

H16A p19 -> (brown) -> [gain pot, 108k] -> (green) -> H9 J2 p4 -> [magic] -> H9 J2 p3 -> (blue) -> front connector