Here is a reprint of a review of the Icom IC-228H posted August 1988.
Since that time, I have enjoyed using the 228H daily without trouble,
and the older IC-28A still works flawlessly. Icom just introduced
the IC-229, a smaller version of the IC-228, so you can probably
get a 228 at a reduced price.
PRODUCT REVIEW: ICOM IC-228H 2M TRANSCEIVER
by Bob Parnass, AJ9S
My Icom IC28A performed very well, and giving it to my wife
afforded me the opportunity to buy another 2 meter radio.
What do I look for in a 2 meter transceiver? Being a
scanner enthusiast, I look for wide frequency coverage on
receive, and reasonable scanning facilities. Reliability
and ease of obtaining schematics and parts are important,
and Icom, Kenwood, and Yaesu score well here.
I prefer 25 watt radios to 45 watt radios for a few reasons:
1. I believe manufacturers overrate their transmitters'
power specifications. Most models use hybrid modules
for the driver/final amplifier stage. As a recent QEX
article points out, the hybrid modules are only 25% -
50% efficient, which means the bulk of the power is
dissipated in the form of heat.1
The heat sinks on today's radios are just not big
enough to dissipate the kind of heat developed during
my typical QSO (conversation). The heat sink on my
old 25 watt Motorola MetrumTM never got nearly as hot
at the heat sinks on late model 25 watt Japanese
radios. My 25 watt Kenwood TR-7800 and IC28A became
very hot during QSOs. Pity those who bought Kenwood's
"45 watt" TM-221A transceiver. It's not until they
read the owner's manual that they learned Kenwood
recommends against transmitting for more than 1 minute
out of 3.
Heat shortens the already finite life of the hybrid
modules, and I've been forced to replace these modules
on various radios, to the tune of over $55 apiece (not
including my labor).
2. It's easier to find power supplies for 25 watt radios,
because they require only 6 - 7 amperes, versus 9 - 10
amperes for their 45 watt counterparts. The smaller
power supplies are less expensive and are easier to
find surplus.
3. Signals from 25 watt transmitters are almost as strong
as those from 45 watt radios.
The IC228A/H series is Icom's replacement for the IC28A/H
two meter radios. The tradition of offering two models at
different transmitter power levels continues, with the 25
watt IC228A and 45 watt IC228H.
The IC228 contains a single VFO, and 20 memory channels.
All the memory channels behave the same, as contrasted with
some Kenwood designs which limit the flexibility of certain
memory channels, while permitting special operations with
others. Each IC228 memory channel can store receive fre-
quency, CTCSS tone, transmit frequency offset, and scan list
lockout.
Unlike Yaesu radios, the IC228 comes equipped with a syn-
thesized CTCSS (PLTM) tone encoder, which is almost a neces-
sity for using repeaters in the Chicagoland area. Any one
of 32 tone frequencies can be selected from the front panel,
and associated with a memory channel or VFO.
Repeater offsets are selectable from 5 KHz through 10 MHz,
and can be stored in memory. You could conceivably store 20
different repeater frequencies in the IC228, each with a
different offset and tone.
I wanted the 25 watt IC228A, but only IC228H models were
available at the time. I'm glad I bought the IC228H high
power model, because an internal potentiometer made it easy
to reduce power output from 45 watts down to 25 watts. The
large heat sink affords extra cooling capacity, and the
final amplifier should last longer. Even so, the heat sink
becomes too hot to hold during a moderately long QSO! Heat
is eventually transferred from the heat sink to the entire
radio case, making the entire radio "untouchable."
The major changes in IC228 circuitry from the IC28 design
involve the microprocessor. The RF circuits remain similar,
using the same transistor lineup in the transmitter stages
and the now familiar Motorola MC3357 IF detector/squelch
chip popular in scanners.
Icom took cues from the Kenwood TM2530 series to improve the
LCD display panel and make the front panel controls visible
in the dark. The display on the IC228 makes use of colored
backgrounds for various fields, and is easier to read than
the display in the IC28.
Unlike the IC28, the IC228 emits a beep tone each time a key
is depressed. Although some people find this feature annoy-
ing in walkie-talkies, the beeps make it more convenient to
operate the IC228 while driving. Icom recognizes freedom of
choice, and permits the user to disable the beep.
The volume, squelch, and tuning knobs, as well as several
buttons, are now backlit - an improvement over the IC28.
The IC28 contained a photocell which automatically varied
the LCD backlighting with changing ambient light levels,
however the newer IC228 permits the user to select from 4
fixed levels of backlighting.
There is no free lunch, and Icom fans had to give up some-
thing in exchange for the new control backlighting: the
plastic front panel and tuning knob on IC228 feel chintzier
than the metal panel and rubber padded knob on the IC28.
Another new feature is a "lock" pushbutton, which disables
the radio's front panel controls. I haven't found this as
useful as the lock slide switch on the DTMF up/down micro-
phone. The up/down pushbuttons on the microphone can be
bumped accidentally in the mobile environment, and the slide
switch prevents unplanned frequency changes.
The IC228's scanning features are on par with, or slightly
above those of other 2 meter transceivers, but not as well
implemented as in "real" scanners. The IC228 scans at the
same speed as the 28 - rather slowly. A reasonable memory
scan, with channel lockout, is provided. This is an
improvement over the early Kenwood TH-215 walkie-talkie
memory scan, which lacked a lockout feature, so one was
forced to scan ALL channels.2
The timer operated scanning in the IC228 causes the radio to
resume scanning 2 seconds after the carrier drops, or after
15 seconds - whichever occurs first. Too bad the IC228
lacks a carrier operated mode, like the feature in the Ken-
wood TM2530, so the receiver would "stay put" until the car-
rier drops.
The IC228 includes the ability to search between 2 frequency
limits, and users of the American versions can select tuning
steps of 5 KHz or more. The search limits are programmed
into a special register pair, so they don't tie up memory
channels. The search will pause as soon as the squelch
opens, which usually brings the receiver to a halt off the
center of the station you want to hear. Unfortunately, Icom
didn't adopt the Kenwood "center tuning" or Bearcat
ZeromaticTM feature, which forces the searching to stop
right on the center frequency. The Bearcat window detector
circuit employs operational amplifiers, fed by the discrimi-
nator signal, to generate a logic level when the receiver is
tuned within 2.5 KHz of center frequency.
When the IC28 was first introduced, it was offered with
either the standard or DTMF microphones, at two different
prices. Apparently, most people wanted DTMF mikes, and a
DTMF microphone is provided with the IC228.
Except for the high heat sink temperatures, the IC228 per-
formed well during a recent cross country trip. With the
radio bolted to the center console of my truck, the receiver
audio output was ample, the display easy to read day and
night, and stations in Pennsylvania and Ohio praised the
transmitted audio quality.
I'm pleased with the IC228, and recommend it.
__________
1. See "RF Hybrid Modules: Building with Bricks," by Bill
Olson W3HQR, in July 1988 QEX.
2. Late vintage Kenwood TH-215 walkie-talkies now come with
upgraded firmware which permits channel lockout. A new
CPU chip may be retrofitted into earlier units, but
Kenwood charges for this service.
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