Thursday, November 14, 2019

Radioddity GD-73A Review

Measuring a mere 115mm x 50mm x 32mm, the palm sized Radioddity GD-73A is a fantastic little radio, ideal for operating via a household Hotspot or into a local Repeater. It is a fully functional Tier II DMR Radio running power levels of 0.5 Watts or 2 Watts.


What is in the box

The Radio comes complete with a charging/programming lead which has a standard USB plug on one end and a mini USB on the other, an earpiece with mic and PTT, Battery and USB Charger and 2600mAH Li-Ion battery pack.

The 2600mAH battery provides sufficient power to afford 16 Hours of continuous use or 48 hours on standby. 

It is possible to store 1024 channels in 64 Zones containing 16 channels in each.  

The stability is            +/- 1.0 ppm,
Channel Spacing        12.5 KHz
Modulation                 11K0F2E (Narrow FM)
                                      7K60FXD   12.5 KHz (Data only)
                                      7K0FXE     12.5 KHz (Data & Voice)
Vocoder                       AMBE+2TM 
Modualtion BER         ≤ 5%
Analog Sensitivity      0.35uV/-116 dBM (20dB SINAD)
                                      0.22 uV/-120 dBm (Typical)
Digital Senstivity       0.3uV/-117.4 dBm (BER 1%)
                                      0.22uV/-110 dBm (BER 5%)
Power O/P                   Low 0.5 W High 2.0 W

The unit will need Firmware upgrading to V1.04 and the accompanying CPS Software. After download ensure that the Firmware upgrading software is run as "administrator". It pays to read the extended manual supplied with the software download. Much time was wasted before this was noted.

Once the Firmware is upgraded it is possible to program the radio. 

The CPS is reasonably simple and conforms to other CPS software. After filling in the general settings with Callsign and DMR I/D, Enter Digital Contacts (Name and TG). Next program channels, and then create a Zone for the respective channels. It is necessary to place channels into a receive list otherwise transmission is possible but reception will not occur. Save the CPS and then load into the transceiver. SIMPLE!

Step 1

Fill in the DMR Radio Field with your call sign and the Radio I.D. with your DMR ID. Ensure that TX Time Out is set to 180 seconds as the components of the network time out beyond 3 mins (180 seconds).


Step 2

Enter Talk Groups that you wish to use. Give each on a Name and it will be a Group Call and the Call ID is the Talk Group designated number as shown below.


Step 3

Assign the Channels and their parameters by filling in the following area for each channel.


Step 4

Assign the channels to a Zone. This locates channels into one bank where they can be selected via up down keys.


Step 5

Fill channels into Receive Group list e.g all Local channels are placed into the EI and UK Receive Group List. 


That completes the programming. Bear in mind that 64 Zones may be programmed with 16 channels in each one. That is a total of 1024. This leaves plenty of scope.

Always save your Code Plug before upgrading the firmware as it may be necessary to reload after the upgrade.

Wot no Keypad? you may ask, but with channels programmed into the device already, the keyboard is seldom used. Programmable buttons P1 and P2 may be assigned to allow navigation and selection of channels in various Zones also selection of High or Low power may be programed to these keys.

Operation through the hotspot was simple and just a case of selecting the required Zone followed by selection of the desired channel, using the up down keys, and then PTT to access. For use via the repeater, selection of 2 Watts is an option although in many cases it was possible to use the low power setting.

The 2600mA will give 16 hours of continuous use or 48 hours of standby time which is more than adequate for most operations.

This is a convenient lightweight handheld to slip in a pocket or bag. The GD-73A has been taken on many trips abroad and kept me in touch with Ireland. The audio out is pleasant and, with the volume turned up full, does not show any signs of distortion. 

As with many DMR handhelds there are Firmware upgrades from time to time ensuring that bug fixes and modifications are carried out.  These are carried out following consultation with users on the Radioddity pages. 

Whilst not at the top end of DMR equipment, the GD-73 is more than adequate for the average requirements of any user. Good clear audio is a key factor and this radio will provide that facility. At $80 this radio will not break the bank and yet will provide hours of Service. if one is only using a hotspot why pay any more for a DMR Radio. Sadly, it does not come with a drop in charger but the fact that it can be charged via a mobile phone charger or the laptop USB may be a plus point.

So far anyone who tried out my GD73A were impressed by the ease of operation and programing. Operation through the Repeater network in the Galway area was perfect and a good point to point QSO over 60 Km was possible using 0.5 watts with both stations almost line of sight