Tokyo Hy-Power HL-350VDX User manual

User’s Manual
144MHz Band
330W Power Amplifier
Model HL-350VDX
TOKYO HY-POWER LABS., INC.

Introduction
The HL-350VDX is a 144MHz Band Linear Power Amplifier with the maximum
output power of 300W (nominal, 330W max.), designed with Tokyo Hy-Power’s
accumulated VHF technologies. This is a completely solid-state amplifier
capable of handling all transmission modes. There are built in such new
functions as an automatic VSWR meter, a new type DC-operated line-flow fan
and a GaAs FET RX Pre-amp with a selectable RX gain.
Main Features
1. Easy to Operate/ Functional Design:
By combining a small heat-sink with a powerful DC-operated line-flow fan,
the HL-350VDX is made light in weight.
It has a fashionable design by putting the heat-sink inside the cabinet.
2. Adoption of Multi-Protections:
It incorporates five kinds of protection circuits developed by our own
advanced technologies. This sophisticated protection gives you a
warning(shut-down) before getting into any trouble.
3. Multi-Metering Method:
The switch selected analog multi-meter on the front panel reads RF OUT (TX
output power), AUTO SWR (standing wave ratio, automatically measured), or
VCC (power supply line voltage), enabling the operation to be comfortably
done at all times.
The high-performance power meter is of a directional coupler type, giving
quite accurate readings.
4. Low-Noise RX Pre-Amp:
It incorporates a low-noise RX pre-amp utilizing a performance-proven GaAs
FET.
The gain of the pre-amp can be selected depending on the receiving
condition. More cozy VHF communication can be enjoyed with the
HL-350VDX.
5. Auxiliary Remote Controlling Function:
A jack for the connection with a remote controller (optional HRC-60) is
provided on the rear panel.
Remote controlling of the power supply, the RX pre-amp and so forth can be
controlled in the remote location.
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Specifications
Frequency Band : 144MHz Band (available for 144-148 MHz)
Mode: FM, SSB and CW
RF Output Power: 300W nominal (330W max.)
RF Input Power: 10/25/50 W (manually selectable)
DC Power Supply: 13.8 VDC
Power Consumption: 42A max. (at 250W output)
Input/Output Impedance: 50Ω
Input/Output Connectors: N-type
Spurious Signal Level: -60dB or less
RX Pre-Amp Gain: -20dB, +6dB, +15dB (selectable)
Accessories: ①RF Output Meter/ Automatic VSWR Meter
②Low-Noise GaAs FET RX Pre-Amp
③Warning Protection Circuit
(protections for overvoltage, overdrive and
mis-match)
④Two-Speed Line Flow Cooling Fan
⑤Reverse DC Power Polarity Protection
Fuses: 20A x2, 1A x1
Attachments: ①Power Supply Cable 8sqmm, 2m long:
red x1, black x1
②ACC 8-Pin DIN Plug x1
③Jumper Cable with N-M connectors:
69cm long x1
④Spare Fuses: 20A x2, 1A x1
Dimensions & Weight 9.6(W) x 3.9(H) x 14(D) inches, Approx. 12.5 lbs.
245(W) x 100(H) x 355(D) mm, Approx. 5.5kg
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Explanation of Features
<FRONT PANEL>
１POWER (MAIN DC POWER SUPPLY SWITCH):
A power switch for the TX amp unit. With the first push, the switch will be locked,
turning the power ON. With the second push, the knob will be released to turn
the power OFF.
２POWER (LED):
Lights when the POWER of TX RF amp unit is turned ON.
３WARNING (LED):
Lights when the power supply to the TX Amp unit is shut down due to overdrive,
overvoltage or mismatch of antenna VSWR etc. After the possible cause of shut
down is corrected, 1 POWER SWITCH may be turned ON again to reset.
４FAN (LED):
Turns ON when the temperature of the heat sink exceeds 50℃. Then, the fan
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starts to run at its full speed. When the heat sink temperature exceeds 70℃due
to a long continuous transmission or any other reasons, the built-in
thermo-sensor will halt the transmission automatically. In that case, do not turn
OFF 1 POWER SWITCH. This is because the fan has to be kept running in
order to cool down the heat sink. Keep 1 POWER SWITCH ON. Transmission
can be restarted once the heat sink temperature is cooled down to the normal
range.
５LO POWER (LED):
Lights when the TX input attenuator is turned on. With the attenuator ON, the
transmission power becomes approx. half of the full output power.
６RX AMP +15dB/ +6dB/-20dB (LED):
Three LED’s show the approximate gain of the R pre-amp at each gain selection.
The gain can be selected by 12 RX AMP SWITCH.
７RF OUT/SWR/VCC (LED):
Indicates the scale of the multi-meter being selected.
８W/SWR/VCC METER:
The multi-meter gives the readings of wattage (RF output power), SWR
(standing wave ratio), and Vcc (DC power supply voltage) respectively. The
output power shown is average power. In the SSB operation, the output power
indicated in the meter can only be approx. 40% of the peak power output. SWR
is automatically shown at any power above 50W as a result of the incorporation
of advanced IC.
９TX (LED):
Lights when the amp is in transmission mode. The LED goes OFF when in the
receive (RX) mode.
１０ RX (LED):
Lights when the RX pre-amp is turned ON.
１１ RF OUT/SWR/VCC (METER SELECTION SWITCH):
Depending on the function to monitor, push the desired switch for the proper
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readings.
１２ RX AMP OFF/-20dB/+6dB/+15dB (SELECTION SWITCH):
Selects the gain of the RX pre-amp. Select the proper gain so that the signal can
be copied most clearly.
１３ POWER LEVEL HI/LO (SELECTION SWITCH):
At 10W and 25W inputs, the power level can be switched to either HI or LO. At
the LO mode, the output power becomes approx. half the HI power. (At 50W
input, the power level cannot be switched to LO.)
１４ MODE FM/SSB (SELECTION SWITCH):
Selects the changeover delay time for TX/RX transition when the operation is
made with the RF key. It takes about 1 second for TX to change to RX state.
When the switch is pressed for FM operation, TX state will instantly change to
RX. For CW, keep this switch pressed ON (SSB position) and for the packet,
keep it pressed OFF (FM position.)
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<REAR PANEL>
Red Black
１５ 13.8VDC (POWER SUPPLY TERMINAL):
Use the included power supply cable for the connection with a stabilized DC
power supply.
Connect the red wire to + and black wire to - .
Make sure to use a power supply with a capacity of 50A minimum.
１６ TX (INPUT CONNECTOR, TYPE N):
Connect the coaxial cable from the transceiver.
１７ ANT (OUTPUT CONNECTOR, TYPE N):
Connect the coaxial cable from the antenna.
１８ ACC (EXTERNAL TX/RX SWITCHING/PTT DIN SOCKET):
Connect DIN plug of hard key control cable from the radio.
Refer to Pages 9 to 11 for pin assignments of 8 pin DIN plug.
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１９ REMOTE (REMOTE CONTROLLER JACK):
With the use of the optional external remote head (Model No. HRC-60), the
following functions can be remotely controlled:
1) Turning ON/OFF of POWER (DC power),
2) Turning ON/OFF of RX AMP (RX pre-amp),
3) Switching of HI/LO (TX output power level), and
4) Resetting of WARNING CIRCUIT shut down.
２０ RF DRIVE 10W/25W/50W (INPUT LEVEL SELECT SWITCH):
Make sure to switch to the correct position depending on the output power of the
transceiver to be used.
Note that an excessive driving power can kill the expensive RF power transistors.
(At the time of shipment from our factory, the switch default is 50W.)
２１ VENT:
For the forced air cooling system, do not block this vent, so that cooling air can
flow smoothly.
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*Wiring Details for REMOTE TERMINAL (remote controller connection jack) are
as follows:
(Don’t connect
ACC CONNECTOR here!)
When viewed
from the outside
of the rear panel→
Terminal No. Noun Connection Details
① RX SW This is connected to the switch of RX pre-amp.
When 13.8VDC is applied, the RX pre-amp will
be turned ON.
② VCC This is connected to the + wire of the power
supply cable.
This pin always supplies 13VDC.
③ HI/LO SW When LO POWER position is selected, this pin
will supply 13VDC.
④ WARNING When WARNING Lamp is turned ON, this pin
will supply the voltage for lighting LED.
⑤ TX When the transmission is being made, this pin
supplies 13VDC (50mA max.).
⑥ GND This is a grounding pin.
⑦ POWER SW This is connected to POWER SWITCH.
When 13.8VDC is applied here, POWER will
be turned ON.
⑧ NC This pin is not connected to anywhere.
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CONNECTION
Power Supply Lead
(Use included cables.)
13.8VDC/50A
Power Supply
50ΩCoaxial Cable
(Use included cable.)
PTT (Hard Key) Cable
Optional Remote Controller
(HRC-60)
50ΩCoaxial Cable
50ΩCoaxial Cable
144MHz Band
T
ransceiver
To Antenna
SWR Meter or
Throughline Watt Meter
red
red
(
+
)
black(-)
black
*Our HP-450
(63A DC power supply) is
available as option.
How to Make ACC Cable (for hard key from the transceiver):
①Processing of Shield Wire Tips:
a) Peel off the sheath.
Sheath
8mm (1/3 inch)
Braid exposed.
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b) Pull off the center wire.
Braid
Center Conductor
c) Peel off the sheath of the center wire tip.
2mm (1/12 inch)
Sheath
②Disassemble DIN Plug:
a) Remove the plastic case from the plug.
Use a screw driver to raise this thin part.
b) Remove cylindrical metallic parts.
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③Solder to DIN Plug.
Solder the braid to the GND pin.
Solder the tip of the center conductor.
(When viewed from the rear end.)
③GND
⑥+DC
⑦SHORT
*Note: If the transceiver externally supplies no voltage (0V, =TX Gnd.) during
the TX, solder the center conductor to Pin⑦ (SHORT), or if it supplies the
positive DC voltage of 2 to 15 V, then solder to Pin⑥ (+DC).
④Re-assemble the plug.
Operation
Check antenna SWR:
(1) Keep the POWER SWITCH of the HL-350VDX OFF.
(2) Turn ON transceiver and tune in a vacant frequency channel.
Then, key to measure the antenna matching conditions with the SWR meter
(Use FM or CW mode.).
(3) If the measured SWR is much higher than 1.5, amp operation will become
unstable.
Check your antenna for the correct resonance.
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TX OPERATION
(1) Before keying the radio, set the switches on the front and rear panel as
follows:
①POWER (Power Switch) →OFF
②RX AMP (RX Pre-Amp Switch) →OFF
③METER SELECT SWITCH →VCC
④POWER LEVEL
(Output Power Select Switch) →HI
⑤MODE (Mode Select Switch) →either FM or SSB
(set to the mode to be used)
(2) Set RF DRIVE (Input Power Level Select Switch on rear panel) to the
maximum power of the transceiver to be used.
Set to one of 10W/25W/50W ranges.
(3) Turn ON POWER Switch of the HL-350VDX. Then, the lamp of the
multi-meter will light.
(4) Read the VCC meter scale.
Make sure that the meter deflection is on the thickened zone (around
13.8VDC).
(5) Key the transceiver. TX Lamp on the front panel will light when the linear
amplifier (TX) is working.
(6) If needed, adjust the RF output power level knob of the transceiver in order
not to overdrive the linear amp.
(7) During the transmission, monitor RF OUT (TX Power) as well as SWR and
VCC (Power Line Voltage) regularly by selecting the Multi-meter Switch, to
see if HL-350VDX is working properly.
(8) Press RX AMP Switch 12 accordingly when the received signal is too weak
or too strong to be copied.
(9) To work the transceiver alone on barefoot, the connection of all the coaxial
cables to and from the amplifier may be left as they are.
Just turn OFF POWER SWITCH 1 .
Then, the output power of the transceiver and the signal being received will
by-pass the amplifier.
If the RX Pre-Amp alone is needed, turn ON RX AMP Switch 12 while
POWER Switch 1 is kept turned OFF.
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Cautions
1. Power Supply:
(1) This amplifier is designed to work from 13.8VDC power supply.
Never connect to an AC line such as 115/120/220/240 VAC.
Such inadvertent connection will kill the amplifier.
(2) Higher supply voltage above 14VDC will lead to damage of the amp.
Keep the power supply at the designed voltage of 13.8VDC.
(3) High current will run with the amplifier at the time of transmission.
Use a stabilized DC power supply with a sufficient current capacity having a
good regulation.
If the regulation of the power supply is poor, the designed maximum output
power will not be achieved.
When extending the power supply cable, try to use cables thicker than 8
square millimeters in the shortest possible length.
The use of thinner cables will result in a voltage drop.
2. Antenna:
(1) Use an antenna that can withstand a continuous 300W transmission.
The use of a lower-power designed antenna can be heated, deteriorating
the SWR as the time passes.
In that case, the WARNING circuit will trip and/or the amplifier may be
damaged.
(2) This model is a high-gain/high-power linear amplifier.
If the antenna is located near the amplifier, RF intrusion will likely occur,
causing troubles due to unexpected oscillation.
Try to locate the antenna far away (as much as possible) from the amplifier.
3. Installation:
(1) Avoid setting the amplifier near the room heater or in the direct sun ray.
(2) Do not block the air vent at the top cover.
Several inches of clearance are needed for the rear panel and wall.
The forced air-cooling fan intakes air from the top cover, and exhausts from
the rear panel.
If the air intake port and/or exhaust port of the amplifier is/are blocked, the
cooling effect inside will deteriorate, causing the inside temperature to be
abnormally high.
Such abnormally high temperature can bring troubles to the amplifier.
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4. Transceiver:
If this amplifier is driven with more than 50W, final power transistors may be
killed due to over-drive.
Check if the output power of the driving transceiver is within the designed
input power ranges of this amplifier.
5. Access To Internal Parts:
This amplifier is carefully assembled and adjusted with sophisticated RF
measurement instruments.
Avoid making access to any of the parts inside.
Or it may cause the trouble of the amplifier.
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Outline of Each Unit
1. TX Unit:
Part of the output power of the transceiver is detected at J101, so that the
carrier controlled solid-state switching circuit turns ON/OFF IC201
(NJM2072D) and Q202 (2SC1959Y), activating the TX/RX change-over
relay.
The RF signal inputted from J101 is amplified from 10W to 80W through
DRIVER AMP Q1 (MRF247), and further amplified to the designed power of
250W to330W through MAIN AMP Q1〜Q5 (MRF247 x4). RF input level can
be selected to 10W, 25W or 50W by the POWER LEVEL SELECT SWITCH
SW1.
At the 10W input, the RF signal is directly connected to DRIVER AMP so that
the maximum gain can be attained.
At the 25W input, the RF signal goes through ATT1 (3dB) to be attenuated for
a proper input level, and is then fed into DRIVER AMP. At the point of either
10W or 25W, the output power can be reduced approx. half by using the
POWER LEVEL SELECT SWITCH.
At the 50W input, RL4 becomes activated to have DRIVE AMP by-passed so
that the RF signal directly drives MAIN AMP to the power of 300W. The
maximum current at the 300W output is approx. 36A where the heat
dissipation is designed to be held as low as possible.
The base bias of each of Q2 through Q5 is controlled by Q7 (2SC1173Y).
The combined power of 250W to 300W is fed through LPF and then sent out
through J102.
A multimeter is incorporated into the HL-350VDX to exactly take hold of the
working conditions. By switching the Meter Switch, W (RF OUT: Output
Power), SWR (Standing Wave Ratio), or VCC (Power Line Voltage) can be
monitored.
Wattage and SWR are detected by a directional coupler.
SWR can be directly read out with the meter at or above a certain output
power (above 50W) as a result of the use of Divider IC203 (NJM4200D). The
divider is stably fed with +5V from three-terminal Regulator IC205
(NJM78L05A), and -5V from DC-DC Converter IC202 (ICL7660CPA).
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2. RX Unit:
The R Pre-Amp utilizes GaAs FET Q6 (MGF1302) and three-terminal Regulator
IC1 (78L05A), so that a high gain amplification with low noise figure is achieved.
When to operate the RX pre-amp alone, with POWER SWITCH turned OFF, turn
ON RX AMP SWITCH. Then, carrier controlling IC201 (NJM2072D) and
switching transistor Q201 (2SA966) will supply voltage to Relay RL5 and the
pre-amp at the RX state, so that a reception gain of approx. 15dB is obtained.
At the TX state, the voltage supplied to RL5 and the pre-amp becomes zero,
where the output power of the transceiver inputted from J101 is outputted
directly from J102 to the antenna.
3. WARNING Circuit:
The almost all part of WARNING circuit is incorporated into the control unit inside
the front panel where tight RF shielding is provided.
Each detection unit utilizes a CM-type directional coupler, Excessive Input
Detection Circuit being installed at the input side of DRIVER AMP, and SWR
Detection circuit being installed at the output side of MAIN AMP.
Each detected voltage is amplified by OP Amp. IC204 (NJM2904D) and the relay
controlling transistor Q203 (2SC3419Y) respectively, and turns OFF Power
Supply Relays (RL6 and RL7) to halt the transmission in case a warning status is
detected.
Two thermal sensors (SW101 and SW102) are installed.
SW102 increases the voltage of the line flow fan from 13VDC to 20VDC causing
the line flow fan to effectively run at its full speed when the temperature of the
heat sink exceeds 50℃.
SW101 turns OFF the power of the carrier controlled switching circuit to halt the
transmission preventing the power transistor from being damaged when the
temperature of the heat sink exceeds 70℃.
The HL-350VDX utilizes an indirect DC main power control circuit where the
power is turned ON/OFF by the Power Relays (RL6 and RL7). Diode D24
(1N5402) being inserted in series to the wound coil of the relays, no current will
be run in the wound coil even if POWER SWITCH is inadvertently turned ON
with a wrong DC power polarity connection.
Thus, the relays will not be activated, so that a safe protection is secured.
16

If 24VDC is inadvertently connected, Zener Diode (05Z16A) will not turn ON
Relay Controlling Transistor Q203 (2SC3419Y) preventing Power Relays (RL6
and RL7) from being activated.
17

18

Trouble Shooting
Following symptoms are not a sign of trouble.
Please refer to the treatment column for correction.
If you still cannot fix the situation, then please call our distributor or contact us for
further technical advice.
Symptoms Causes Treatments
1) Power connector
prematurely connected.
Properly connect it again.
2) Power lead prematurely
connected.
Check it for contact points.
3) Wrong polarity connection. Properly connect it again.
DC Power won’t
be turned on.
4) Fuse blown. Replace with new one.
1) Microphone gain
potentiometer or carrier level
controller of XCVR turned
down to the lowest level.
Turn the knob to half of the
full level.
2) The protection of HL-350VDX
has tripped.
(WARNING LED is lighting.)
Turn OFF the power.
Once the trouble is
corrected, turn ON the
power to have the
protection restored.
3) Misconnection of input
power.
Reconnect it properly.
No output power
is obtained.
4) The power switch of XCVR is
not turned on or XCVR is out
of order.
Check XCVR.
1) The power supply voltage
drops while in transmission.
Check the voltage in the
transmitting stage.
Output power is
less than
designed specs. 2) The output power of
Transceiver is less than
needed.
Check the output power of
XCVR and increase the
output power to the needed
level.
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