I've been following on youtube the reviews of this radio, released by various reviewers and users, starting from spring 24.
And I finally decided to buy one from Aliexpress where I paid 190 Euros + 11 euros for import duties.
The devices is full of features out of which the most interesting to me are:
- the coverage up to 999 MHz starting from 153 kHz.,
- two LNA,
- an antenna tuner,
- low pass and high pass band filters,
- 3 possible external antennas: 1 for VHF/UHF (with a SMA connector), 1 tunable loop for LW, MW and SW with a 3.5mm jack on the top panel and 1 external antenna with a 3.5mm Jack input on the back panel, this is conected to a further pass band tuner with 3 positions (MW, lower SW, upper SW), these are alternative to an internal ferrite rod for LW and MW and an quite long telescopic whip mounted on the top panel of the radio.
Reception mode : AM WFM NFM USB LSB, but not everywhere, SSB reception is available only between 2.3 and 30 MHz. VHF/UHF only in NFN, FM in WFM, LW/MW only in AM, SW in AM/USB/LSB.
On top of these a large number of gadgets: scan function, 1600 memories, sound equalizer, selectable bandwidth, different colours for the main screen, a second smaller screen with VU-meter and signal strength detection (RSSI and SNR), sleep function, timer, alarm, squelch, sub bands, recording function on microSD, bluetooth, an android/iPhone app to controll the radio from remote, update of the firmware through PC connection....a million stuff. I would recommend to watch on youtube for a detailed description.
But how it works???
Not so bad, it has quite good sensitivity and not desperately noisy when the Low Passband filter is selected for the SW reception. Air band: good, WB: who knows? there's no WB in Europe. UHF I could not tune anything, but I don't know what to tune where. VHF on the 2 m band I could recognize the IQ2MI CW beacon but in NFM because SSB reception is not available in VHF. MW not bad too with its own ferrite rod. LW: uhm....so and so.
During the afternoon and early evening I could reach rank 2 in DSC reception on 16804.5 kHz.
Lowlight: it mutes while tuning, it mutes a lot!
The antenna selection and tuner section
I always recommend to read carefully the instructions booklet provided with the radios. But at the same time is exactly what I never do. I read the quick start guide when available and I give a diagonal read to the remaining pages. With the HRD C-919 understanding how the antenna settings work is quite complicated, there's a schematic which one gets with the radio, mine one is in Chinese and even looking at the block diagram the understanding takes some time.
As of today, my understanding is the following:
the rear antenna socket surely works for MW and SW, the switch control (MW-SW1-SW2) on the back of the radio allows to pre-select the band on which the antenna is receiving. Now, selecting from the antenna select button on the front panel under the main screen:
the loop
with "Internal"
is possible to use the antenna tuning knob on the right panel for the received band, selected with the rear switch. I have to admit that it is quite effective
Apparently (to my understanding) using the 3.5mm socket on the top panel and swithcing on the breaker to activate it, the signal is not routing anyore through any of the LNA installed and signals are much lower. Honestly speaking I do not see any advantage in SW using the 3.5mm socket on the upper panel, unless a strong signal is injected.
All settings related to the manual RF channel selection in the center of the picture above, are available for operating the radio while using an antenna connected to the 3.5 mm socket in the back panel. All those selections can be activated with the settings button in the front panel above-right the tuning knobs while the screen shows:
The lower left part of the schematic is for the built in ferrite rod antenna, it works as in any other portable device: tune and turn the radio body for better reception.
SSB Reception
This is somethnig that is really annoying me: I see this also in the first versions of the ATS20/25 receivers based on the SI 4732.
This is somethnig that is really annoying me: I see this also in the first versions of the ATS20/25 receivers based on the SI 4732.
For example I need to tune DSC 8414.5 khz and decode the signal with YaDD: tuning upward from 8413 kHz I get the 1000 Hz tone at 8413.9, tuning downward from 8414.5 I get the 1000 Hz tone at 8413.6 kHz. And on top of this the postion of the 1000 Hz tone is even influenced by the chosen bandwith.
However: if they could eliminate the muting while tuning and extend SSB reception modes to all bands, this would be a very cool receiver.
