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The FD-460UH (See Fig 1) is a hand held UHF FM transceiver. It appears to be an FD-460A with frequency range of 410-480MHz.
| Item | Specification | Measured | ||
| 410MHz | 432MHz | 479MHz | ||
| Frequency accuracy (ppm) | +/-2.5 | -2.9 | ||
| Sensitivity (µV 12dB SINAD) | 0.16 | 0.21 | 0.11 | 0.15 |
| Power out (W HI) | 4/5 | 3.8 | 4.5 | 4.0 |
| Power out (W LO) | 2.2 | 2.9 | 2.4 | |
| Deviation (kHz) | <5 | 3-4 | ||
| CTCSS Deviation (kHz) | 0.6 | |||
Table 1 sets out the specifications and test transceiver performance at three frequencies across its operating range. The red text highlights failure to meet specification.
| Item | Specification | Measured | ||
| 410MHz | 432MHz | 479MHz | ||
| Frequency accuracy (ppm) | +/-2.5 | 0.5 | ||
| Sensitivity (µV 12dB SINAD) | 0.16 | 0.14 | 0.13 | 0.12 |
| Power out (W HI) | 4/5 | 3.8 | 4.0 | 3.6 |
| Power out (W LO) | 2.5 | 2.7 | 2.4 | |
| Deviation (kHz) | <5 | 3-4 | ||
| CTCSS Deviation (kHz) | 0.6 | |||
Table 2 sets out the specifications and test transceiver performance at three frequencies across its operating range. The red text highlights failure to meet specification.
The supplied battery is a 5 cell NiMH battery specified at 1200mAh capacity.
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A new battery was cycled twice then discharged at a constant current of 0.375A, 50% of the specification high power current drain.
The discharge took 3.2h and indicated a capacity of 1200mAh.
This test indicates that the probably supports towards 3.2h talk time at a 50% duty cycle.
The documentation does not specify a recharge time. The measured time to recharge from flat was 9.5 to 10h.
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Fig 3 shows the transceiver in the desktop charger cradle. The lower rows of buttons are squeezed in by the cradle, see the red circle which highlights a key partially operated by the cradle fit. The transceiver cannot be reliably used in the cradle (eg for monitoring) as slight movement or vibration causes one of the lower row of keys to operate. It appears that the cradle is designed for transceivers without keys, and has been pressed into service for the FD-460A series.
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Fig 4 is a screenshot of the programming software.
Deficiencies with the software include:
Nevertheless, having guessed how to use it, it seemed reliable, if tedious to fill in manually.
Loading channel tables is tedious work and prone to error. Some applications lend themselves to loading the channel table from a script.
| <?component error="true"
debug="true"?> <package> <job id="vbs"> <script language="VBScript"> set WshShell = WScript.CreateObject("WScript.Shell") if WshShell.AppActivate("FD Serials") then WshShell.SendKeys( "^{HOME}") 'CB WshShell.SendKeys( "^{HOME}") f=476.425 for channel=1 to 40 WScript.Sleep 50 WshShell.SendKeys( "{HOME}") WScript.Sleep 10 fr=f+(channel-1)*0.025 ft=fr if(channel=22 or channel=23) then ft="{DEL}" 'lockout tx on data channels WshShell.SendKeys( fr & "{ENTER}" & ft & "{ENTER}OFF{ENTER}OFF{ENTER}NO{ENTER}YES{ENTER}NO{ENTER}") WScript.Sleep 100 next 'CB repeaters for channel=1 to 8 WScript.Sleep 50 WshShell.SendKeys( "{HOME}") WScript.Sleep 10 fr=f+(channel-1)*0.025 if(channel>8) then ft=fr else ft=fr+30*0.025 end if if(channel=22 or channel=23) then ft="{DEL}" 'lockout tx on data channels WshShell.SendKeys( fr & "{ENTER}" & ft & "{ENTER}OFF{ENTER}OFF{ENTER}NO{ENTER}YES{ENTER}NO{ENTER}") WScript.Sleep 100 next end if </script> </job> </package> |
Fig 5 shows an example WSCRIPT for loading the channel table. Due to the lack of short cut keys to select the channel table input grid, the cursor MUST be located anywhere in the grid for this script to work properly.
Scripting was reliable, the interface was quick enough to not require delays within or between the SendKeys calls.
The supplied English manual is basis, nicely laid out, but not well explained.
The manual was not availble for download in electronic format (eg PDF).
Feidaxin's web site confusing, not clear, especially the software download page.
Good, works well, nice audio, robust clip, good modulation, positive PTT.
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The SMA(f) - BNC(f) adapter supplied by 409shop had a shorter thread projection than the supplied antenna. The threads barely engaged the transceiver (less than three turns) and inner conductor contact was made only 1.5 turns before bottoming. The part is a poor fit, it is cheap but should be considered incompatible.
The USB programming cable uses a Prolific USB-RS232 bridge. It is a neat and low cost solution to programming from a computer without a COM port (eg most modern notebook computers).
Unfortunately, the driver's for these type of bridges (Prolific, FTDI) allocate a COM port ID to each chip that is ever introduced to the computer. This could quickly use up a large number or port allocations which are quite difficult to reallocate. For this reason, it is better to use a conventional serial programming cable if the computer has a COM port, or to share a single USB-RS232 bridge with various programming cables.
The supplied software disk was corrupted.
The Lighter adapter cable for the desktop charger was inexpensive, seemed well made and had an easy to change integrated 3AG fuse.
On-air performance seems acceptable, there is little IMD breakthrough though the trial area does not suffer from major city noise floor problems.
The CTCSS decoder is a little slow in opening.
The keyboard lock is not persistent, it has to be reset every time the transceiver is powered up.
The following features are often found on competitive transceivers, but are not on the FD-460UH:
Overall, the transceiver is a sound implementation, appears tough and robust, and works well although slightly out of spec in some respects. It is moderately featured, but lacks some features found in competitive devices.
The frequency range of 410-480MHz isn't commonly found in this market segment.
The desktop charger cradle does not properly suit the transceiver.
Software and documentation let the product down.
After market accessories are low in cost, and some work well, but some have quality issues.
Quite credible for its price.
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