Every year, the number of new HAM members in the country reaches tens of thousands, and in recent years, it has grown geometrically. As a qualified HAM, you must go through the procedures of registration, training, examination, receiving membership card operation certificate, checking machine, issuing operation call sign. In some areas, all equipment needs to pass the machine inspection to check the emission indicators to obtain a license. In some areas, as long as the equipment has a model approval code and is a new device, the default indicators are qualified and the license can be issued directly. Many HAMs are curious about the inspection, and a few are worried that the inspection will not pass. How can amateur radio enthusiasts quickly inspect the inspection? This article will tell you.
First you have to understand the content and standards of the inspection machine
For amateur radio stations, only indicators such as frequency, power, bandwidth, and spurs are detected. These indicators have no primary, secondary, or sequential distinction. Generally, the standard equipment that has obtained the type approval certificate can pass the test. Inspection is free!
1, FM transceiver
FM transceiver, which is a VHF / UHF radio station commonly used by radio enthusiasts. In the amateur machine inspection, even if only the frequency, spurious and other indicators are detected, the editor has drawn a table for your reference.
Take the test frequency tolerance as an example to explain how to use the above table. Frequency tolerance is the maximum allowable deviation of the characteristic frequency of the emission from the reference frequency.
A class A enthusiast carries a hand set, and sets channel CH1 to a frequency of F = 438.500MHz, then finds the line corresponding to 438.500 MHz from the table above as the line 430MHz, and the hand corresponds to the last column, which takes the value "7". Then the frequency tolerance = 438.500 × 106 × 7 × 10-6 = 3069.5Hz, usually 3kHz is taken in the actual test. If the measured frequency value is f, then -3kHz≤Ff≤3kHz is qualified.
From the inspection results of the past ten years, it is common for inspection failures due to excessive spurious standards. Many enthusiasts don't pay attention to the stray excess, because it feels that the device can communicate normally, but it is not true. For the spurious excess equipment, it will interfere with other devices, including radio equipment and non-radio equipment.
2. Short-wave single-sideband equipment
For enthusiasts who have obtained Class B and above operating certificates, they can carry short wave equipment to check the machine. The detection criteria are as follows:
What are the problems that often occur during the inspection?
1, equipment identification is not qualified: Some fans choose the machine has not obtained a model approval certificate, or the approval certificate is false, such a device test pass rate is very low, and will affect their own future use. It is recommended to use products from regular manufacturers, and you can log in to the China Radio Management Website () approval bulletin for inquiry. Domestic machines have applied for an approval code for the D9000 platform. The approval code is: CMIIT ID: 2017FP5750. You can use this device to inspect the machine.
2. The test indicators are unqualified: Some fans choose the machine itself to be of poor quality or aged during this period, so it can only be replaced by new equipment and retested. There are also other unqualified indicators that can be avoided according to the actual situation:
How to quickly check the machine?
1. Learn to use your new equipment in advance.
Some HAMs bought new equipment and took the test site to test it before they had time to read it. In fact, this was very time consuming. First of all, the testing engineer is not obliged to debug the equipment for radio enthusiasts. In addition, new equipment is constantly emerging. The testing engineer may not be able to set the parameters of each machine. Therefore, it is recommended that enthusiasts learn to use their new equipment in advance. Talk to other enthusiasts, and then come to the machine.
2. Set the frequency and power that meet the requirements in advance and apply to yourself.
Before testing, the hams try to refer to the frequency and power adjustment equipment indicators in the "Frequency and Power Tables Allowed by Amateur Radio Stations of All Grades in Beijing" to set the power as low as possible.
3. When carrying out the inspection, bring along the documents, the tested equipment and accessories.
During the inspection, enthusiasts should bring the original second-generation ID card, information management card, and application form for setting up the station in duplicate, and paste the copy of the second-generation ID card. Bring all equipment and accessories, such as hand microphones, panels, and panel connection cables, to avoid borrowing from each other on the site; keep the power supply of the equipment normal, such as the battery of the handheld should be charged in advance, and the power cord of the platform should be prepared (power is available on site) ).
4. Simultaneous detection of multiple groups and independent queuing
In the field test, in order to shorten the waiting time for everyone, the test staff will send multiple groups to hold multiple test instruments and provide testing services for the majority of enthusiasts. These groups of personnel are in a parallel relationship. You can choose any team with fewer people to perform Detection. After passing the test, go directly to the last workbench to submit the form and stamp.
After passing the inspection, the inspectors uniformly report the batch of fan information to the local radio authority, enter the stage of approving the station, and wait for the completion of the relevant documents. Finally, notify the fan to obtain the radio station license through the service window.
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