STF279069 Comments By STF279 On EN300 6722 Draft 1

stf279_069 comments by stf279 on en300 672-2 draft 1 (1) a. general points the draft hs conforms closely to the guidance. several mi

STF279_069
Comments by STF279 on EN300 672-2 Draft 1 (1)
A. General Points
The draft HS conforms closely to the guidance. Several minor obvious
editorial corrections are needed and these are not explicitly
commented on save to list them here:
*
All Guidance notes and STF Notes should be deleted
*
All references should be included in the list of references and
referred to consistently. (Some references cited in the HS have
numbers which are inconsistent with those listed in the list of
references)
*
Ensure that all references are “specific” (i.e. dated or version
numbers quoted.)
*
All abbreviations, definitions, symbols that are used should be
included ion the appropriate lists, but it is possible to avoid
long lists of such items by referring to the lists in Part 1 –
although it seems that very few abbreviations etc are used in this
document, so a complete explicit list appears preferable
Some more significant, but still broadly editorial, comments are
listed below. These are only in the form of suggestions for the
information of the rapporteur. As always, final decisions on the
structure and content of the HS rest with the TB (TC-ERM, in this
case) who will be guided by the Guidance material but may override it
with justification.
B. More specific Comments
1. It is understood why you have added the paragraph in upper case in
the Foreword. I suggest a minor change to it as follows, as “technical
procedures and limits” is too restrictive and not really terminology
used in RTTE):
The present document specifies only essential requirements of certain
aeronautical VHF equipment in the context of Article 3.2 of the R&TTE
Directive. For use in civil ground to air communications ….
Some reviewers might argue that inclusion of this paragraph goes
against the guidance in EG301 399 clause 7.1.3 (Material to be avoided
in HSs) which includes in its list of statements to avoid: “4)
statements implying obligations outside the scope of the standard…”
but I personally feel that this statement in the Foreword is helpful
and implies no confusion as to the role of the document especially as
the Foreword should never not include normative material.
2. However, I suggest editorially that the paragraph mentioned above
might fit more comfortably immediately below the paragraph which lists
the two parts (rather than above it as in the draft).
3. The paragraph immediately following that mentioned to in comments
1) and 2) above, should be completed to read as follows:
“The present document is part 2, of a multi-part deliverable covering
Ground-based VHF hand-held, mobile and fixed radio-transmitters,
receivers and transceivers for the VHF aeronautical mobile service
using amplitude modulation, as identified below:”
4. My personal view is that it would be helpful to include the actual
frequency band limits explicitly instead of (or as well as) by
indirect reference to ICAO annex 10 volume V (1996) [1] - . (In other
words, and in Scope should be replaced by actual
frequencies.)
5. In 4.2.1.1 (and elsewhere). It would habe been better to define the
requirement in terms which do not require reference to the method of
measurement and then refer to the method of measurement in the
subsequent clauses such as 5.2.1.1. However, there are many other
standards which only define the requirement in terms of the method of
measurement. So this is a point of style, which only you can consider
the merit of - provided that you can satisfy ERM on this point – and
precedent is oin your side.
6. I personally am concerned by the inclusion of so many receiver
parameters in an Article 3.2 RTTE standard. This might be challenged
by ERM - but it is up to them to decide what is reasonable in this
standard. Some commentators would be strongly against inclusion of any
receiver characteristics (apart from spurious emissions) and the
guidance in EN 201 399 clause 1.4 says:
“Usually … receiver parameters are not to be specified … Exceptions …
where a receiver parameter directly affects the operation of a
transmitter … with consequent risk of generation of harmful
interference….”
It is not clear how this would be interpreted and how ERM would judge
TCAM would view this. With manual listen before talk systems, it is
not clear whether receive equipment (including receive only equipment)
can be considered to directly affect the operation of the transmitter.
7. Assuming that you retain the receiver parameters, I suggest for
editorial consistency that you put each parameter in a separate
clauses 4.2.2.1, 4.2.2.2, 4.2.2.3 etc corresponding to the separate
parameter defined in Part 1 clauses 8.1, 8.2, 8.3 etc. Similarly, I
suggest similar Part 1 clauses referenced under 5.3.2.2 should become
separate clauses 5.3.2.2, 5.2.3.3, 5.2.3.4 etc for ease of reference
and to maintain consistency with the transmitter clauses.
8. Annex A will require to be updated to align with these changes in
the body of the document.
9. The Note towards the end of Annex A may (and should) be simplified
as follows as there are no “O” or “X” entries in the E/O column in the
Table above:
NOTE: Rows designated “E” collectively make up the Essential Radio
Test Suite and these shall be performed as specified with satisfactory
outcomes as a necessary condition for a presumption of conformity.
10. It perhaps appears a pedantic point, but as the HS addresses “transmitters,
receivers and transceivers” and so all requirements related to
transmission characteristics apply only to equipment with a transmit
capability – and likewise reception characteristics apply only to
equipment with a receive capability. To be precise, the table in Annex
A should be changed to reflect this as indicated in red overleaf – in
addition to any changes implied by comment 8 above.
CJ Cant
STF279
22 February 2006
Harmonized Standard EN 300 676-2
The following essential requirements and test specifications are
relevant to the presumption of conformity under Article 3.2 of the
R&TTE Directive
Essential Requirement
Requirement Conditionality
Test Specification
No
Description
Reference:
Clause No
U/C
Condition
E/O
Reference:
Clause No
1
Frequency error
4.2.1.1
C
Note 1
E
5.3.1.1
2
Carrier power
4.2.1.2
C
Note 1
E
5.3.1.2
3
Adjacent channel
power
4.2.1.3
C
Note 1
E
5.3.1.3
4
Broadband noise
4.2.1.4
C
Note 1
E
5.3.1.4
5
Tx spurious
emissions
4.2.1.5
C
Note 1
E
5.3.1.5
6
Intermod
attenuation
4.2.1.6
C
Note 1
E
5.3.1.6
7
Keying transients
4.2.1.7
C
Note 1
E
5.3.1.7
8
Rx Sensitivity
4.2.2.1
C
Note 2
E
5.3.2.1
9
Rx Spurious
emissions
4.2.2.2
C
Note 2
E
5.3.2.2
Note 1: This requirement only applies to equipment with a transmit
capability
Note 2: This requirement only applies to equipment with a receive
capability