THIS TRANSCEIVER HAS AN ISSUE AND NEEDS SERVICING BY A TECHNICIAN
It is very important that those interested in this transceiver to read EVERYTHING in this detailed description so that you can gain an idea of what needs to be done!
HISTORY:
In a previous life I was heavily involved in professional communications (Maritime) and on a personal level, Amateur radio (ex VK2DWF and now relinquished for some years) so of course I collected radio equipment, even very early AM Citizen Band equipment. HF frequencies were always of interest, particularly with phenomenons such as "skip" allowing communications over great distances with very low power, when the conditions were "right"
These days I couldn't imagine anyone using such equipment and if on HF they would use gear such as CODAN's and like, however it can still be fun to "listen around", particularly in the evenings when the HF bands can "open up"
Of course, along with those strange sounding long distance signals you will hear loads of atmospheric noise - it's part of the deal on HF, particularly during our latest round of thunderstorms which we have recently experienced!
NO fancy bells & whistles, meaning no DTMF, Control Sub-Tones, SELCAL or Voice scrambling - this is a plain old low power AM HF transceiver, with fixed 40 channel selection and of course no BFO's etc so it's not of much use for SSB either.
If you are looking for a transceiver that you can power up and start talking immediately to your fellow "inmates" on a local FM repeater, this equipment is NOT FOR YOU!
If however you are an Amateur or technician with skills in communications electronics, this may be a fun "thing" to play around with.
Please read on for the details of this REALISTIC TRC-415 mobile transceiver ...
REALISTIC - COMMUNICATIONS TRANSCEIVER
Designed & made in Taiwan
Marketed by Realistic (Intertan Australia)
Intended for the Australian market - Black face panel
Dates from the 1980's ~ 1990's period
Model: TRC-415
Analog AM HF Transceiver
Frequency range: 27Mhz (fixed channels totally 40 in number)
Not user programmable
RF power output: 4W maximum
Internal speaker fitted ** See note below about this though!
Basic front panel with rotary Volume (which integrates with the ON-OFF switch), rotary Channel control and Squelch adjustment
Display is a nice Ruby Red LED numerical display with a bar graph running along the lower edge (indicating RX signal strength and TX RF power output)
PL259 Antenna connector
External Speaker connector
DC (nominally 13.6V) is supplied directly into the transceiver (no DC plug/socket) and the DC lead is supplied but without any in-line fuse fitted
ITEMS NOT SUPPLIED:
A microphone is NOT supplied but is available as a separate item HERE
Mounting bracket and thumb screws are NOT supplied
DIMENSIONS:
115mm wide x 175mm depth x 30mm height (small slim line case)
WEIGHT:
800g
COSMETIC CONDITION:
USED
CLEAN
NO physical damage to the folded steel body or the front panel
Light/medium oxidisation "stains" to the top cover ONLY, this doesn't affect the integrity of the casing but it doesn't look "pretty". Looking inside there is what appears to be soft paper sheeting used as an insulator (case to the electronics) and I have left this alone.
not serious and there is no oxidisation on the underside (inside of the plate)
DC lead is of a good length but has no in-line fuse holder fitted.
I took a quick look inside the unit (easy to access by removing 4x side screws), all clean and it does not appear to have been "worked on" previously.
TESTING:
This is the part that really matters!
I only had a 12V supply at hand for testing and at a low current capability but at least it enabled me to test the transceiver (within limitations)
Same goes for an antenna, just a simple 'whip' antenna used for testing.
** Audio note: while the transceiver works as it should (TX and RX) WITHOUT the microphone plugged in, there will be no local audio from the internal loudspeaker. Plug in the microphone and the internal speaker will come alive.
Power ON (rotate the Volume control) and the very retro RED display comes alive
No sound yet because the squelch is fully clockwise, wound it back and greeted with 'white noise" - all good.
Channel changing (using the larger rotary knob) was easy and working fine, each click changed the channel indication on the display
Switching around the channels I can hear "strange sounds" which are likely to be adjacent services "break-through" - no conversations, although this doesn't surprise me as I am in metro Sydney and I would be extremely surprised if anyone was using 27Mhz AM nearby in the middle of the day. I also listened around in the evening, heard more 'noise' but no conversations. I confirmed that the white noise level significantly increased when the antenna was connected and decreased when removed - this is normal for a working HF RX.
Pushed the PTT on the microphone (not supplied with this unit but available separately) and the bar graph lit up right across the display, meaning full RF power output. I spoke into the microphone and the LED display varied as it should AND I could hear my audio on my local receiver/scanner.
I had full output across all the selected channels, 26.965 to 27.405Mhz
That's about the best I could do, my sig gen's have all gone elsewhere and even the RF power meters are no longer with me ...
HOWEVER ...
I then noticed something a bit strange ....
While in receive, after a 'while" (random timing) the audio level of the white noise would slowly fade away then suddenly jump back up again to normal. I then tried transmit when the audio had faded down, yep - no TX either. Only when the audio came back up did the TX work properly.
While this was happening I was monitoring the current being drawn by the TRC-415, it did not change (up or down) and I got the distinct impression it was as though a capacitor was charging and discharging - I wouldn't be surprised if the problem revolved around a cap, 30 ~ 40 years is a long time to expect a capacitor (particularly electrolytic) to not be leaky.
I am not interested in radio servicing these days, no test gear to speak of, bad eyes these days so I am not about to go fault finding .... that is the new owner's task
I DO have the full (readable) schematic though - so at least you wouldn't be working "blind"
So there you have it, a real antiquity from the world of public AM communications equipment - offered for fun as I really couldn't imagine anyone would seriously be chin wagging using AM HF CB radio these days.
