Commercial in Confidence
Smartfind EPIRB service manual
Page 17
3.3. Message read
To comply with SBM and annual maintenance the service provider must verify the EPIRB
message. This can be done with a "Message Reader". A typical instrument is the
ARG5410. This model will be used to describe the process. Operation of the Reader is
detailed in its handbook and will not be repeated here. The procedure is as follows:
1. On the Reader select RECV mode
2. Position the Reader approx. 1m (3 feet) from the EPIRB
3. On the EPIRB press the TEST button
4. After about 4 seconds the Reader should then beep and report DECODING
MESSAGE followed by S’TEST OK
5. The Reader will revert to its Menu. Select VIEW mode
6. Use
←
→
keys to view the decoded 406MHz message content
7. Confirm the frequency was within 406.020 – 406.030
This proves the 406MHz transmitter is radiating within the correct frequency band. If the
ARG5410 Reader is not used, then another facility for measuring the 406MHz frequency
must be provided (a spectrum analyser for example).
8. Confirm the 15 digit ID agrees with EPIRB rear identity label UIN
This proves the 406MHz transmitter is modulating correctly and the EPIRB is programmed
with the correct identity. If the ARG5410 is not used then another facility for message
decoding must be provided (other message readers).
9. Confirm the Flag state and the Serial No / MMSI / Callsign agrees
Typical screen
Q
11:25
Mesg#11 S’TEST OK
ID: 9D0D071D3B00013
406.0257 MHz PASS
Common problems
Audio tone
Will not be heard with Smartfind product.
Frequency
If outside limits, repeat self test a number of times.
(Provides a warm up time). Repeat test.
Bad frame
This error message occurs if the Reader fails to synchronize.
This occurs approx. 10% of the time. Repeat test multiple
times. Move location of EPIRB/reader.
Also note that an exhausted reader battery causes bad
frames.
Normal mode
It is possible to message read in live mode provided the EPIRB is in a screened
enclosure. In this case the Reader reports NORMAL OK and the first 3 bytes of the full
hex message are FF FE 2F… instead of the usual FF FE D0… for self test mode.
GPS messages
The transmitted message will change once the GPS location has been confirmed. On
some older message readers this will result in a HEX ID which does not correspond to
the one given for the EPIRB under test.
