Question For Jim Weir

In article , "W P Dixon" wrote:
You might check out the ICOM A5 Sport. It is the alkaline battery version
without many extras. It goes for about $220.
tom

That definitely seems to be the popular answer Jim. Thanks for your input.
May try the handheld contraption in my volksplane. Just would not want an
expensive radio in it . Now the Thatcher CX4 on the other hand

Patrick
student SPL
aircraft structural mech

"W P Dixon" wrote in message
...
Jim,
Is it practical,

No.


possible

Yes.


and legal

Yes.


1to build a radio for your own homebuilt
airplane? I can't see paying 1000 bucks for a panel mount unit for a
volksplane.


You will spend a thousand hours (literally) designing it, and ten thousand
dollars doing the test and fees to certify it.



Jim

In article ,
W P Dixon wrote:
Jim,
Is it practical, possible and legal to build a radio for your own homebuilt
airplane? I can't see paying 1000 bucks for a panel mount unit for a
volksplane.


Is it "possible"? Yes.

Is it 'legal'? Depends on how you do it. The only people that can just
go off and build a transmitter/transceiver are licensed
"amateur radio service" operators, and then *only* for
equipment that operates in the 'ham' bands. *Everything*
else requires FCC approval, in one form or another -- unless
it is _very_ low power, operating in specified frequency
ranges.

Is is "practical"? Not if the objective is to save money. It would have
to be 'accepted' by the FCC. Either "type accepted",
which would let you do production-line work, and sell
on the open market, Or _individually_ approved, for
that specific radio only,

*either*way*, you're looking at costs that are well
into 5 figures. And probably around two years of
paperwork.

Is it 'legal'? Depends on how you do it. The only people that can just
go off and build a transmitter/transceiver are licensed
"amateur radio service" operators, and then *only* for
equipment that operates in the 'ham' bands. *Everything*
else requires FCC approval, in one form or another -- unless
it is _very_ low power, operating in specified frequency
ranges.

That is NOT true, elsewise how would we be able to build the prototypes that
we test for the type acceptace procedure. That is, if I can't build an
aircraft band transceiver then I can't test it to get type acceptance which
means that I can't produce them, and if I can't produce them, then I can't
sell them... Get the circular argument?

There ARE provisions in the rules for a legitimate manufacturer to build and
test prototypes for licensing procedures.





Is is "practical"? Not if the objective is to save money. It would have
to be 'accepted' by the FCC. Either "type accepted",
which would let you do production-line work, and sell
on the open market, Or _individually_ approved, for
that specific radio only,

I am not aware of anything in parts 1, 15, or 87 that allow single-unit
approvals.



*either*way*, you're looking at costs that are well
into 5 figures. And probably around two years of
paperwork.

Well, not really. I've done half a dozen type acceptances where the costs
(excluding my labor) are well under a thousand dollars. HOWEVER, you have
to be very creative about how you do it.

Jim

In article ,
RST Engineering wrote:

Is it 'legal'? Depends on how you do it. The only people that can just
go off and build a transmitter/transceiver are licensed
"amateur radio service" operators, and then *only* for
equipment that operates in the 'ham' bands. *Everything*
else requires FCC approval, in one form or another -- unless
it is _very_ low power, operating in specified frequency
ranges.

That is NOT true, elsewise how would we be able to build the prototypes that
we test for the type acceptace procedure. That is, if I can't build an
aircraft band transceiver then I can't test it to get type acceptance which
means that I can't produce them, and if I can't produce them, then I can't
sell them... Get the circular argument?

There ARE provisions in the rules for a legitimate manufacturer to build and
test prototypes for licensing procedures.

*sigh* "requires FCC approval, in one form or another" would include FCC
provisions granting limited operations privileges -- for testing, etc., even
on a 'blanket' basis -- under the auspices of a properly licensed engineer.
The stock 'restricted' radio operator's license of a pilot isn't sufficient.

The situation is not as extreme as aircraft manufacture, where you have to
have a design cert. first, and then a separate cert. for the production line.
admittedly. But "Joe Sixpack" off the street does have to jump through
hoops before he qualifies as a 'legitimate manufacturer'. That's what
earns him the 'FCC approval' to build "test"/"prototype" radios.

Or, if you prefer, I'll modify the statement to to "the only people that
can just go off and build a transmitter/receiver _and_put_it_into_'everyday_
_use'_operation_, are ham operators."


Is is "practical"? Not if the objective is to save money. It would have
to be 'accepted' by the FCC. Either "type accepted",
which would let you do production-line work, and sell
on the open market, Or _individually_ approved, for
that specific radio only,

I am not aware of anything in parts 1, 15, or 87 that allow single-unit
approvals.

I know of experimental one-of-a-kind transmitters that were granted operating
licenses. Without "type approval". These were, admittedly, _not_ on
aircraft band.


*either*way*, you're looking at costs that are well
into 5 figures. And probably around two years of
paperwork.

Well, not really. I've done half a dozen type acceptances where the costs
(excluding my labor) are well under a thousand dollars. HOWEVER, you have
to be very creative about how you do it.

If you got out for "under a thousand dollars" excluding your labor, it
sounds like you have/own/operate your own FCC-certified testing facility,
is that correct?

If one has "resources already in place", that have been amortized as "sunk
costs" from 'doing it previously' on other work, and hold the requisite
professional engineering accreditations so that you don't have to out-source
the technical requirements, I'll grant the sub-$1,000 (exclusive of labor)
possibility. For a _first-time_ effort, however -- as the original
poster was proposing -- using that accounting methodology, one must include
_all_ the costs of getting those resources in place, That's _how_ they
get to be 'sunk' costs for the subsequent projects

Would you care to estimate what your 'first time' costs would be, starting
from having just a basic set of 'hobbiest' tools?



You, yourself, said in another post, that it would take the OP more than
"a thousand hours, and ten thousand dollars", to 'legally' do his project.

Since labor has been excluded, if the OP does the design work himself,
it's "free". there's maybe a couple of hundred dollars in parts. and
he assembles it himself (that's "free" labor, too.)

"Robert Bonomi" wrote in message
...
In article ,

*sigh* "requires FCC approval, in one form or another" would include FCC
provisions granting limited operations privileges -- for testing, etc.,
even
on a 'blanket' basis -- under the auspices of a properly licensed
engineer.
The stock 'restricted' radio operator's license of a pilot isn't
sufficient.

Double *sigh*. There is no such thing as a "properly licensed
engineer". Nor is a restricted radio operator's license a reality in
today's pilot world. Where have you been for thirty years?


If you got out for "under a thousand dollars" excluding your labor, it
sounds like you have/own/operate your own FCC-certified testing facility,
is that correct?

That is correct.




If one has "resources already in place", that have been amortized as "sunk
costs" from 'doing it previously' on other work, and hold the requisite
professional engineering accreditations so that you don't have to
out-source
the technical requirements, I'll grant the sub-$1,000 (exclusive of labor)
possibility. For a _first-time_ effort, however -- as the original
poster was proposing -- using that accounting methodology, one must
include
_all_ the costs of getting those resources in place, That's _how_ they
get to be 'sunk' costs for the subsequent projects

Would you care to estimate what your 'first time' costs would be, starting
from having just a basic set of 'hobbiest' tools?

Sure. Spectrum analyzer through 4 GHz. on the surplus market $800.
Antennas from 30 to 3000 MHz. using water pipe and copper foil another $50.
Antenna masts using 4x4 doug fir another $50. Low freq receiver to do the
30 kHz. through 30 MHz. stuff another $200. 12 volt batteries to obviate
the line filters $50. Switching power supplies to power the test equipment
$50. Frequency counters on the used market $50. Oscilloscopes another
$200. Sig gen another $200. What are we up to? Less than $2K? And this
is the FIRST time around. Next time is simply the expendables.

Jim









You, yourself, said in another post, that it would take the OP more than
"a thousand hours, and ten thousand dollars", to 'legally' do his project.

Since labor has been excluded, if the OP does the design work himself,
it's "free". there's maybe a couple of hundred dollars in parts. and
he assembles it himself (that's "free" labor, too.)

"RST Engineering" along with
"Robert Bonomi" wrote in message

If you got out for "under a thousand dollars" excluding your labor, it
sounds like you have/own/operate your own FCC-certified testing
facility,
is that correct?

That is correct.

As an aside, is this facility/capability available for hire if someone
wanted
to do some pre-certification testing or qualification?

Bill

I did my last certification/type acceptance using this "facility" almost 15
years ago, and have pretty well dismantled it. It could be put back
together in a couple of weeks, but until I have the need to do so, it will
remain dormant.

If you wanted to do the grunt work, I could show you how to do it. It is,
so far as I know, still in the FCC database as an approved pattern range.
You have a couple of holes to dig, some plastic pipe and woodwork to do,
and a couple of tables to build.

The thermal chamber was also discarded...along with the temperature
measuring setup. That would need to be rebuilt. Depending on the size of
your device, it can be trivial or a pain. We used a Coleman cooler with a
light bulb as the thermal source, dry ice as the cooling source, and a
computer fan to keep the chamber at a constant temperature. The
"thermometer" was a diode calibrated at the freezing point of water, the
boiling point of water, and extrapolated to the temperatures we needed. The
reality check was with a real thermometer borrowed from the local college's
chemistry lab.

The answer is that if you want to spend a couple of hard weeks at it, you
are welcome to use it. The calibration curves are still accurate and I have
the exact locations of the antenna masts marked...just not dug and sleeved
for the antenna mast. There are better ways of doing it than 4x4 lumber,
and I might like to explore that.

Jim



"Netgeek" wrote in message
...

"RST Engineering" along with
"Robert Bonomi" wrote in message

If you got out for "under a thousand dollars" excluding your labor, it
sounds like you have/own/operate your own FCC-certified testing
facility,
is that correct?

That is correct.

As an aside, is this facility/capability available for hire if someone
wanted
to do some pre-certification testing or qualification?

Bill

Jim,

This is about the best offer I've heard in a long time (and quite
generous on your part)! You're on. It will take me a few months
(minimum) to get my act together and finish off some of these
designs (assuming that I can 8-).... and then I'd be glad to dig
some holes, schlep lumber, whatever.....

"RST Engineering" wrote:

If you wanted to do the grunt work, I could show you how to do it. It is,
so far as I know, still in the FCC database as an approved pattern range.
You have a couple of holes to dig, some plastic pipe and woodwork to do,
and a couple of tables to build.

It's a deal..............

The thermal chamber was also discarded...along with the temperature
measuring setup. That would need to be rebuilt. Depending on the size of
your device, it can be trivial or a pain. We used a Coleman cooler with a
light bulb as the thermal source, dry ice as the cooling source, and a
computer fan to keep the chamber at a constant temperature. The
"thermometer" was a diode calibrated at the freezing point of water, the
boiling point of water, and extrapolated to the temperatures we needed.
The
reality check was with a real thermometer borrowed from the local
college's
chemistry lab.

I can handle this.... just need to get the beer out of the cooler long
enough
to make it happen. Hmmmmm......might require more than one cooler.

The answer is that if you want to spend a couple of hard weeks at it, you
are welcome to use it. The calibration curves are still accurate and I
have
the exact locations of the antenna masts marked...just not dug and sleeved
for the antenna mast. There are better ways of doing it than 4x4 lumber,
and I might like to explore that.

Agreed. Given the choice of sending some units off into the ether to be
tested at some "regular lab" - or camping out in Grass Valley for a 'couple
weeks doing some grunt work - it's a no-brainer... Additional bonus - the
wife can head off to spend some time with her friends in Napa (so it's
an easy sell 8-).....

I'll get in touch as soon as it looks like there's something worth testing.

Thanks again! I'll put you in for an "Elmer Award" with the ARRL and
the EAA...8-)

Bill