What ham can be without a test bench. Well until recently this ham had
been without a real test bench for way too many years. I still had the
VOM and DMM and even an osiloscope, but not a real test bench since moving
to Lakewood in 1985 when I sold most of my test equiopment for lack of
enough space to put it all in.
THE OLD TEST BENCH
Between 1975 and 1985 I built two large 10x3 foot test benches in the
cellar of my parents house (with my Fathers help) that hosted the
equipments pictured below. There was no way I was going to get this
stuff into a small ranch with no basement that would soon also occupy
my child bride to be !
I had all the required equipment to perform calibration, alignment and
repairs to most amateur and commercial radio equipments on the time.
In the photos among other things one can see a GE 100 Amp DC power supply, Hewlett
Packard Audio and RF signal gererators, Hammerlund receivers (coverage of DC through UHF).
Tektronics Osciloscopes and Hewlett Packard and Singer Spectrum analyzers (DC to 40Ghz),
HP RF Milivolt meter and various other meters, bridges and signal sources.
However, I disposed of most of the equipment when I moved into my current home as
I had no basement and did not plan to continue the type of experimentation and
electronics work that demanded such equipement.
THE CURRENT TEST BENCH:
When it comes to test bench work these days my main interest is the building
of VHF/UHF FM repeater systems and the restoring old Yaesu FT-101x series
transceivers and amplifiers as well as reparing whatever drops dead for
either lack of use or heavy use. As such I have recently built a new test
bench around two-way radio specific service equipments in particular.
As we entered the year 2001 I started to get refocused on various aspects of
Amateur Radio and realized that I once again required a real test bench. Not
having the room that I once did has necessitated a more compact set up and
luckily the equipments have gotten smaller over the years. I have a number of
equipments that overlap each other in features and frequency ranges for multi
purpose applications.
My bench is based on a heavy 1 1/4 inch thich formica work table with an
adjustable steel frame for height above floor dimensions. The table top is
30 deep by 48 inches wide. On on the table top is a 34 x 48 inch 3M static
control table mat (color green) with wrist strap table top grounding system.
I also have a 16 x 16 inch square 1/2 inch thick Teflon plate (color white) that
sits on top of the 3M anti-static mat for use with heavy items that could damage
the 3M mat. Fop this purpose I drape Clauss Electronics Division "Softy"
anti-static work mats (color white) over the teflon plate.
I monitor my A.C. power line with a Viz RMS line monitor which has a calibrated
scale of 100-140 volts. I also have a Northern Technologies A.C. power conditioner
as my A.C. outlet for A.C. powered equipments under test.
For D.C. power sources I have four analog power supplied in the bench.
An Astron RM-12, 13.8v D.C. 12 amp peak unit. An Astron RS-50M 13.8v D.C.
50 amp peak supply with a heavy 8 gauge dual outlet fused power buss to
the bench for powering and testing high power trasmitters and amplifiers.
I also have two variable voltage bench top supplies, a 0-50 volt 2 ampere
New Jersey Electronics (NJE) model LVC 50-0.5 laboratory power supply
(made while my father work for the company and was production manager)
and a 4.5-15 volt 25 amp Pyramid Pase III supply.
The main piece of equipement is a Motorola R-2002D/HD Communications Analyzer, commonly referred to as a Service Monitor.
I found a fairly good deal on a surplus unit from the U.S. Navy used by
the Navy Metrology and Calibration METCAL
that was kept in tip top shape and came complete with all accessories.
Next is an older Eaton AILTECH FM-100 Service Monitor.
Then there is a Wiltron 640 RF Network Analyzer (under the Ailtech)
which includes such desirable features as a 1 to 1500MHz RF sweep
generator which covers the entire range in one continuous sweep is
also part of the bench. This item serves mainly for the tuning of
duplexer and filter cavities and testing of transmission lines.
Hewlett-Packard 1743A 100Mhz oscilloscope:
A general purpose portable, lab quality oscialloscope.
Leader LBO-518 100Mhz oscilloscope:
A general purpose portable, lab quality oscilloscope shown seated
on top of the R2002D.
Hewlett-Packard HP 5300A/5303B 525 MHz Frequency Counter:
The 5300A Measurement System Mainframe unit provides the system power,
reference frequency, display, counting logic and timing control required
for plug-in's. Features include: 6-digit dot matrix display, overflow
indicator, standard timebase, external timebase input and BCD output as
a standard rear panel output. The crystal frequency is 10MHz with a
typical stability of less than plus or minus 2 parts in 106. Oscillator
output is 10MHz, approximately 1 Vrms at rear panel BNC, 100 ohm source
impedance.
HP 5300A measuring system mainframe with a 5303B frequency counter
module that has a 6 digit dot matrix display, standard time base,
external time base input & BCD output as a standard rear panel output.
The 5303B has 2 input channels: Channel A (CW or Burst) has a range of
DC to 525MHz prescaled by 8 and Fixed Sensitivity 100 mV rms sine wave,
dc to 500MHz. 125mV rms sine wave, 500MHz to 525MHz. Signal must pass
through zero Channel B (CW or Burst) has a range of 50Hz to 80MHz
direct and Automatic Sensitivity 25 mV rms sine wave, 100Hz to 50MHz.
50mV rms sine wave, 50 Hz to 100 Hz and 50 MHz to 80 MHz. Sensitivity
is adjusted automatically by Automatic Gain Control.
Hewlett-Packard HP 5315A 100 MHz Universal Counter:
The versatile 5315A has a range from 0.1 Hz to 100 MHz (on A & B inputs).
Time interval delay: holdoff, variable delay of nominally 500 microseconds
to 20 ms between "START" (on Channel A) and "STOP" (on Channel B). All
measurements have up to 8 digit resolution. The 5315A Universal Counter
measures signals over 0.1Hz to 100MHz range. The unit measures Period:
10ns to 105Sec; Time Interval: 100 ns to 105 Sec; Time Interval Average:
0 ns to 105 Sec; Time Interval Delay: holdoff, variable delay of nominally
500µs to 20ms between START (channel A) and STOP (channel B); and Ratio:
0.1Hz to 100MHz, both channels. A totalize function with manual or external
gating is also provided. All measurements, except totalize, have up to 8-digits
resolution. Two channels provide time interval measurements
Motorola R-1150B Code Synthesizer II for external tone signaling.
The Code Synthesizer is a universal signaling encoder that generates
tone digital signaling codes used in two-way radios, paging, and car
telephones to include Single Tone, 2 Tone, 5/6 Tone, MTS, IMTS, DTMF,
Tone Control, DPL, Digital Paging tests, with 8 digit readout. In
single tone it operates as a general purpose audio oscillator.
Motorola S-1350A portable watt meter.
Motorola R-1033A Test Set:
A Motorola radio specific test set for metering of receiver and
transmitter stage A.C. or D.C. voltages and current parameters
for radio alignment.
It also provides accurate measurements of audio output for
receiver quieting or Sinad measurements. A self contained
speaker permits audio monitoring and a built in PTT switch
or optionally either a Motrac or Mostar wired microphone can
be used for PTT and actual voice transmissions. Also built in
is a 1Khz oscillator for Sinad testing.
I was lucky that when purchased I received complete cable
sets and documentation with the unit for the testing of Mitrek,
Micor, MSF-5000 and other Motorola radio types.
Motorola S-1339A RR Millivolt meter:
RF Milvolt Meter, analog, mirrored scale, 50 ohm impedance, frequency
range of 10 kHz to 1.2 GHz. RF level measurement sensitivity ranging
from .1-3000 mV (100uV to 3V) RF. It also can measure in dbm, ranging -50 to +20dbm.
Motorola R-1013A Sinad meter:
Built in A.C. powered or DC powered bench top Sinad meter for
receiver sensitivity measurements. Sinad or rather Signal-to-Noise-And-Distortion
ratio is the ratio of the input signal to the sum of noise and harmonics:
SINAD = 20 log (SignalRMS / (Noise + Harmonics)RMS).
This specification must include the input level used to determine the specification
and the bandwidth over which the specification is measured.
Motorola Audio Oscillator/Distortion Analyzer:
An older piece of equipment that provides a stable audio range oscillator
with analog distortion analyzer. AC or DC powered.
Marconi model TF-2304 FM Deviation/AM Modulation meter.
Bird Electronic Model 43 Thruline Wattmeter
Aa portable insertion-type instrument. It accurately measures forward or reflected power in coaxial
transmission lines under any load condition. Power range is 100mW to 10 Kw using Bird plug-in elements
with an accuracy of +- 5% of full scale. Frequency range, depending on elements is from 0.45 to 2300 Mhz.
In addition to the standard elements listed below for testing exciter
and power amplifier levels, I also have a special Bird slug with a
50 db down port over the range of 25-1000Mhz at up to 500w. This
sampler slug has a female BNC output to test instrumentation such
as an oscilloscope, spectrum analyzer etc.
As my interest is in HF, 6m, 2m, 1.25m and 70cm mainly, my standard
elements include:
2-30Mhz 500w 500H
Bird Termaline Dummy Load Model 8251:
High-Power Oil-Dielectric 50 ohm dummy load with an N type
female connector termination.: Power Rating: 1000W continuous,
Frequency Range & VSWR: 1.1 max. dc to 1000MHz, 1.25 max. 1000-2000MHz
1.3 max 2000-2400Mhz over an ambient temperature range: -40°C to +45°C,
Load coolant: 1.1 gal. (4.1 liters) silicone oil and weight of 25 pounds.
Bird Termaline Dummy Load Model 8135:
I have two 150 Watt continuous rated dry 50 ohm dummy loads that
cover a frequency range up to 2.4 GHz. with an N type female
connector termination.
Bird Termaline Dummy Load Model 82A:
I have two older 51.5 Ohm impedance 500 watt coaxial oil dielectric
cooled rated DC - 2.5Ghz @ VSWR 1.1 Max. Rated 2000 watts with cooling,
with an N type female connector adapater termination.
I also have one Bird model 8085 50 ohm 50 watt Termaline load with male
N connector.
I have four (4) Celwave 25w continuous 100w intermittent N male loads,
one with a 50db down signal tap.
Telewave model 44A diretional watt meter.
General Radio Company 1862B Megaohmmeter.
Fluke 12B Digital Multimeter
Micronta digital multmeter model 22-195A with transistor tester
Attenuators:
I have one Hewlett-Packard 355C .5 watt 50ohm DC-1000mhz 1-12db
with BNC connectors.
I have two (2) JFW Industries model 50R-080 0-12db 1 db step
attenuators with N connectors. Frequency range and power rating
are unknown at this time.
For information on my commercial amateur radio products please click here to send e-mail or
visit the main website.
2-30Mhz 1.0kw 1000H
2-30Mhz 2.5kw 2500H
2-30Mhz 5.0kw 5000H
25-60Mhz 100w 100A
25-60Mhz 1.0kw 1000A
40-50Mhz 1w 040-1
95-150Mhz 2.5w - - -
110-160Mhz 1w - - -
100-250Mhz 5w 5C
100-250Mhz 25w 25C
100-250Mhz 100w 100C
100-250Mhz 500w 500C
200-500Mhz 5w 5D
200-500Mhz 10w 10D
200-500Mhz 500W 500D
400-1.0Ghz 100w 100E
Entire contents Copyright © 1999-2001 by Stephen B. Hajducek, N2CKH. All Rights Reserved Worldwide.