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Meat Plow
Guest

Thu Jan 13, 2011 1:30 am   



On Wed, 12 Jan 2011 13:11:41 -0800, Jeff Liebermann wrote:

Quote:
On Wed, 12 Jan 2011 20:21:54 +0000 (UTC), Meat Plow <mhywatt_at_yahoo.com
wrote:

I've also had grounding problems with this radio. Makes the audio howl
when you turn it up past 50% on 70 centimeters.

That's not grounding. It's microphonics. The 440 PLL is getting
mechanically modulated by the audio from the loudspeaker. Get the phase
right and you have a howling oscillation. I use bees wax, hot melt
glue, or if desperate, RTV, to reduce the mechanical sensitivity of the
VCO. You might also try a rubber foam pad between the PCB and the front
panel to acoustically decouple the PCB.

Those that suggested the fix called it grounding. That's all I know.

Quote:
Other than this, the radio has worked well, the batter has held up
remarkably and the audio is robust. I also have a dual band FT-60. Rock
solid radio, very loud audio with little distortion. Bought it back in
2006 from AES. They had a special on the radio and drop charger that I
couldn't resist.

The local animal rescue volunteer group all got licenses and
standardized on the FT-60. It's a better radio than the VX-5 but is too
much for many of the users to operate. It also has the irritating WIRES
function which must be disarmed before it can be used. They would have
been better off with channelized commercial radios but the ham stuff was
cheaper.

Yeah the WIRES/ inet radio is crap. And the beacon function for other
hams radios to alert when your in range. Forget what that's called maybe
ARS? It's got a lot of good functions besides that. I'd like to see a
battery voltage display option that keeps it on the screen past power on
like the VX-5 has.

Quote:
I bought a Diamond SRH320A antenna for it. I've worked repeaters 50
miles away outdoors on 2 meters with that HT.

About 2 years ago, I gave a demo on HT antennas. It didn't take much to
demonstrate that bigger is better, no matter how weird looking. I
placed a field strength meter at a fixed distance from the radio, and
tried various antennas. The best on 440 MHz was an AMOS/Franklin
monstrosity that I conjured for the occasion. It was about 1.5 meters
overall, with the HT in the middle, which had to be held horizontally.
On 2m, it was a flex PCB antenna I had etched into a sheet of mylar,
representing something like a 3 element Yagi. The usual base and center
loaded dual band rubber ducky antennas were horrible by comparison, but
were greatly improved by the addition of a counterpoise.
http://www.k6gph.org/index.php?
option=com_content&view=article&catid=1&id=10&Itemid=7
Incidentally, I brought an inflatable UHF loop yagi antenna that used a
1 meter long rubber sausage shaped balloon for mechanical support and
insulation. I didn't have time to try it as I ran out of time. (Hint:
I use the stock rubber ducky as everything else is too big and clumsy).

Unless your repeater is a few miles in radius from you a small duck is
good enough. My closest repeater is 12 miles. I have a Cushcraft AR270
about 15 feet above the roof with Belden 8319 coax @ about 560 foot.
Does a great job. Also have at about the same height a Cush Ringo AR6.
I sometimes serve as our district's backbone liaison for Skywarn and talk
to the NWS on 6. Make me feel like a big shot.

--
Live Fast, Die Young and Leave a Pretty Corpse

Meat Plow
Guest

Thu Jan 13, 2011 3:10 am   



On Wed, 12 Jan 2011 15:26:19 -0800, Dave Platt wrote:

Quote:
In article <pan.2011.01.12.23.02.44_at_lmao.lol.lol>, Meat Plow
mhywatt_at_yahoo.com> wrote:

I've been fighting off the temptation to just remove the SMA, drill
out the hole, and replacing it with a BNC.

That might be difficult considering the SMA on the VX-5 is recessed.
Also I don't know if there's room inside bor the butt end of a BNC.

What I was thinking, was mounting the BNC on the top of the case...
there appears to be enough metal surrounding the recessed-SMA mounting
hold to support it. Stick the "butt end" of the BNC down through the
SMA mounting hole and into the case. I'd probably need to fix it into
place with epoxy rather than using a nut, though.

I'd rather just place a new SMA and nut with thread grip then use the
factory duck. I didn't have problems until replacing the factory duck
with a poorly fit OEM.

Quote:
It'd certainly be an invasive mod, and probably quite unnecessary. I
wouldn't do it unless I didn'd mind trashing the radio - or at least the
case. If I even run into a "beater" VX-5, with an intact case but a
fried radio, I might buy it and just try modding the case.

I've had to tighten up the SMA on mine maybe twice. But I also use an
OEM antenna and I'm not sure if that contributes because the OEMS don't
seat all the way down in. I ended up putting a small grommet around the
bottom of the SMA on the radio so the antenna tightens down on the
chassis rather than just the threads. Seems to have cured the problem.

I generally use an SMA-to-BNC adapter, with a grommit-like arrangement
made out of a couple of thicknesses of rubber tubing, and then use an
aftermarket BNC antenna.

I guess it just depends how careful you are. I've placed the dual band
FT-60 on the VX-5 now since 6 meter is out of range for an HT here and
it's been stable for years. The stock duck with the screw on tip isn't
pocket or belt material for sure. Bu the FT-60 duck seems to cooperate
nicely for what my needs are.



--
Live Fast, Die Young and Leave a Pretty Corpse

Wild_Bill
Guest

Thu Jan 13, 2011 2:42 pm   



I might be tempted to try an external switch to find out what the circuit
requires for more predictable/reliable operation.

The rubbery buttons' pads are conductive, obviously, but rarely low ohms in
resistance. With a common momentary switch and a 1k (or 200, 470 etc) series
resistor, the unit may operate just fine.
Then check the resistance of the existing switch to see if it's near the
improvised resistance that works well.

The rubbery switches' conductive pads generally increase dramatically with
use. Looking at aged conductive pads, they often develop a glazed-looking
surface from being pressed repeatedly.

I often scuff them very lightly with very fine abrasive (approx 600 grit) or
one of those fiberglas pen scuffing tools, but very lightly.. just enough to
remove the glaze from the pad.
The resistance comes back down, and the conductive pads work fine until they
get glazed again.. many uses later (like keyboard keys, IR remote buttons
etc).

--
Cheers,
WB
..............


"Meat Plow" <mhywatt_at_yahoo.com> wrote in message
news:pan.2011.01.11.19.31.34_at_lmao.lol.lol...
Quote:
Yaesu VX-5R tri-band hand held. Momentary contact power on/off button.

I've owned this radio for 9 or 10 years. Recently I have to push several
times on this rubber on/off button to get the radio to come on. But it
always takes just one touch to turn it off. And the radio works fine
otherwise including all the other buttons. Just have to play around
pressing the button maybe three/four/five times. Sometimes it powers on
when pressed once! But always shuts off with just one easy push.
This indicates to me that it's not a problem with button contact but
rather a microprocessor problem.

Discuss.



--
Live Fast, Die Young and Leave a Pretty Corpse


Michael A. Terrell
Guest

Thu Jan 13, 2011 2:59 pm   



Wild_Bill wrote:
Quote:

I might be tempted to try an external switch to find out what the circuit
requires for more predictable/reliable operation.

The rubbery buttons' pads are conductive, obviously, but rarely low ohms in
resistance. With a common momentary switch and a 1k (or 200, 470 etc) series
resistor, the unit may operate just fine.
Then check the resistance of the existing switch to see if it's near the
improvised resistance that works well.

The rubbery switches' conductive pads generally increase dramatically with
use. Looking at aged conductive pads, they often develop a glazed-looking
surface from being pressed repeatedly.

I often scuff them very lightly with very fine abrasive (approx 600 grit) or
one of those fiberglas pen scuffing tools, but very lightly.. just enough to
remove the glaze from the pad.
The resistance comes back down, and the conductive pads work fine until they
get glazed again.. many uses later (like keyboard keys, IR remote buttons
etc).


I used to repair Commodore 64 computers. The keyboards had the same
type of switches. I would clean them with Isopropyl alcohol, then wipe
them across a piece of cloth (like Denim) to remove the dead surface.
You could see how much was removed, because live surface didn't leave a
streak on the cloth.

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

Jeff Liebermann
Guest

Thu Jan 13, 2011 6:07 pm   



On Wed, 12 Jan 2011 23:30:32 +0000 (UTC), Meat Plow
<mhywatt_at_yahoo.com> wrote:

Quote:
Those that suggested the fix called it grounding. That's all I know.

I suppose it's possible to play with the grounding enough to affect
the feedback phase of the microphonics, but the main cause is
mechanical. Generate a UHF carrier with something, and set the radio
to that channel with a fairly strong carrier. Put the radio to your
ear and beat on the case with something. Can you hear the pounding
coming out of the speaker? If yes, you have microphonics.

Quote:
Yeah the WIRES/ inet radio is crap. And the beacon function for other
hams radios to alert when your in range. Forget what that's called maybe
ARS? It's got a lot of good functions besides that. I'd like to see a
battery voltage display option that keeps it on the screen past power on
like the VX-5 has.

I think it's Alinco that has the ultrasonic sound generator that keeps
the mosquitoes away. Now, that's innovation.

Quote:
Unless your repeater is a few miles in radius from you a small duck is
good enough. My closest repeater is 12 miles. I have a Cushcraft AR270
about 15 feet above the roof with Belden 8319 coax @ about 560 foot.
Does a great job. Also have at about the same height a Cush Ringo AR6.

I think we have more repeaters than active hams in the area. Choice
is a good thing, until it's time to program the radio. The small
rubber duck is usually enough. For anything more, I sometimes play
mobile repeater using the radio in my vehicle.

Quote:
I sometimes serve as our district's backbone liaison for Skywarn and talk
to the NWS on 6. Make me feel like a big shot.

We have some local hams that are members of Skywarn. There's also a
ham station at the NWS office in Monterey, CA. I'm (fortunately) not
involved. We have micro climates here due to the mountains. It's not
unusual to have a heavy rain that's only about a mile wide.


--
Jeff Liebermann jeffl_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Meat Plow
Guest

Thu Jan 13, 2011 11:21 pm   



On Thu, 13 Jan 2011 08:42:11 -0500, Wild_Bill wrote:

Quote:
I might be tempted to try an external switch to find out what the
circuit requires for more predictable/reliable operation.

The rubbery buttons' pads are conductive, obviously, but rarely low ohms
in resistance. With a common momentary switch and a 1k (or 200, 470 etc)
series resistor, the unit may operate just fine. Then check the
resistance of the existing switch to see if it's near the improvised
resistance that works well.

The rubbery switches' conductive pads generally increase dramatically
with use. Looking at aged conductive pads, they often develop a
glazed-looking surface from being pressed repeatedly.

I often scuff them very lightly with very fine abrasive (approx 600
grit) or one of those fiberglas pen scuffing tools, but very lightly..
just enough to remove the glaze from the pad.
The resistance comes back down, and the conductive pads work fine until
they get glazed again.. many uses later (like keyboard keys, IR remote
buttons etc).

I've cleaned others with a piece of felt and alcohol. Right now it's
mildly irritating only. Once I have to mess with it longer than a few
seconds I'll peal the HT apart and clean it. The innards are pretty
small. I have to wear a stereo magnifying visor to see the tiny screws
holding the keypad backing board to the case.



--
Live Fast, Die Young and Leave a Pretty Corpse

Meat Plow
Guest

Thu Jan 13, 2011 11:37 pm   



On Thu, 13 Jan 2011 09:07:11 -0800, Jeff Liebermann wrote:

Quote:
On Wed, 12 Jan 2011 23:30:32 +0000 (UTC), Meat Plow <mhywatt_at_yahoo.com
wrote:

Those that suggested the fix called it grounding. That's all I know.

I suppose it's possible to play with the grounding enough to affect the
feedback phase of the microphonics, but the main cause is mechanical.
Generate a UHF carrier with something, and set the radio to that channel
with a fairly strong carrier. Put the radio to your ear and beat on the
case with something. Can you hear the pounding coming out of the
speaker? If yes, you have microphonics.

No, tapping on it will not induce micro-phonics but will often lessen the
howl. Once the radio is on, the howl goes away, maybe after 10 minutes.
I'm no newbie to micro-phonics. Some of the old PLL-02a chassis CB radios
would howl if you turned up the volume. But you could also hear a high
pitch whine in the howl if you tapped on the chip.

Quote:
Yeah the WIRES/ inet radio is crap. And the beacon function for other
hams radios to alert when your in range. Forget what that's called maybe
ARS? It's got a lot of good functions besides that. I'd like to see a
battery voltage display option that keeps it on the screen past power on
like the VX-5 has.

I think it's Alinco that has the ultrasonic sound generator that keeps
the mosquitoes away. Now, that's innovation.

No kidding LOL!

Quote:
Unless your repeater is a few miles in radius from you a small duck is
good enough. My closest repeater is 12 miles. I have a Cushcraft AR270
about 15 feet above the roof with Belden 8319 coax @ about 560 foot.
Does a great job. Also have at about the same height a Cush Ringo AR6.

I think we have more repeaters than active hams in the area. Choice is
a good thing, until it's time to program the radio. The small rubber
duck is usually enough. For anything more, I sometimes play mobile
repeater using the radio in my vehicle.

I sometimes serve as our district's backbone liaison for Skywarn and
talk to the NWS on 6. Make me feel like a big shot.

We have some local hams that are members of Skywarn. There's also a ham
station at the NWS office in Monterey, CA. I'm (fortunately) not
involved. We have micro climates here due to the mountains. It's not
unusual to have a heavy rain that's only about a mile wide.

We have it here due to severe thunderstorms with large hail, damaging
winds, localized flooding, micro-bursts and tornadoes. In April of 2002
a tornado narrowly missed my place. Winds took out windows, ripped siding
off houses one street down, took down large trees behind my property,
then jumped a 1/4 mile and continued. The same tornado traveled about 15
miles landing then rising taking out a whole neighborhood 8 miles before
it got here. So we have the potential for some damaging storms. I
remember in 1999 I had just purchased a Dodge 4x4 in the spring. I was
out chasing a storm around and got pelted by some golf ball sized hail.
That ended my chasing days. I don't have a beater that I care about
looking like someone took a hammer to it.




--
Live Fast, Die Young and Leave a Pretty Corpse

Jeff Liebermann
Guest

Fri Jan 14, 2011 9:58 pm   



On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow
<mhywatt_at_yahoo.com> wrote:

Quote:
No, tapping on it will not induce micro-phonics but will often lessen the
howl.

Well, if it were "grounding", then banging on the case would have no
effect (unless there were some screws loose).

Incidentally, I tried my VX-5 turn on/off times. It took about 1
second to turn on, and the same to turn off. Pushing the button to
turn off was *NOT* instantaneous. I had to hold it for 1 sec. It's
been like that since new, so there's been no deterioration. At this
point, I don't know if it's a firmware issue, settings issue, or dirty
keyboard. Save, reset and reload seems the easiest to do first.

Quote:
Once the radio is on, the howl goes away, maybe after 10 minutes.

Something is getting warm perhaps?

Quote:
We have it here due to severe thunderstorms with large hail, damaging
winds, localized flooding, micro-bursts and tornadoes.

That's why I like California. Other than earthquakes and government,
we don't have much in the way to disasters here.

Quote:
... I had just purchased a Dodge 4x4 in the spring. I was
out chasing a storm around and got pelted by some golf ball sized hail.
That ended my chasing days. I don't have a beater that I care about
looking like someone took a hammer to it.

Ouch. I've never even seen a tornado, so I have no idea what it might
be like. Raining golf balls sounds like no fun. Yes, Skywarn has its
place in your part of the country.

--
Jeff Liebermann jeffl_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Meat Plow
Guest

Sat Jan 15, 2011 12:34 am   



On Fri, 14 Jan 2011 12:58:42 -0800, Jeff Liebermann wrote:

Quote:
On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow <mhywatt_at_yahoo.com
wrote:

No, tapping on it will not induce micro-phonics but will often lessen
the howl.

Well, if it were "grounding", then banging on the case would have no
effect (unless there were some screws loose).

From what I've read these radios, maybe the first batch had grounding
issues and the fix was to provide a better ground. If you have some time
google VX-5 grounding issue. I haven't done it yet so I can't post any
reference links.

Quote:
Incidentally, I tried my VX-5 turn on/off times. It took about 1 second
to turn on, and the same to turn off. Pushing the button to turn off
was *NOT* instantaneous. I had to hold it for 1 sec. It's been like
that since new, so there's been no deterioration. At this point, I
don't know if it's a firmware issue, settings issue, or dirty keyboard.
Save, reset and reload seems the easiest to do first.

Yeah by immediately I meant within a second. Compared to 10 sometimes 30
seconds to get it to come on it seemed pretty immediate to me :)

Another couple things; if the radio if left off for a couple days it
takes more button-play to get it to come on. Also when I charge it off
the cig lighter cord, the words 'now charging' appear and when done the
RX/TX light turns amber and 'charge complete' is displayed. This tells my
some micro processing is going one when the radio is off. I guess you
could call it a soft-off/soft-on. Obviously with a touch pad some standby
processing is needed to interpret the call for on. But without delving
into the operating theory it's hard to tell exactly but easy to guess.

Quote:
Once the radio is on, the howl goes away, maybe after 10 minutes.

Something is getting warm perhaps?

The RF out device sinks on the back but I think the warming and expanding
of the radio in general creates a better ground for whatever is not
getting a good ground. The radio does not have to be transmitted, it can
just RX during this period and eventually the howl will stop. And the
howl is only on .70cm. This would indicate problems other than grounding.
Or not Smile It's only a minor annoyance and I actually do a lot of SW QSX
on that radio and only use it moderately on VHF. And it's been doing the
howl for years. Neither the howl or delayed on are a big issue until
either interfere completely with the operation.

Quote:
We have it here due to severe thunderstorms with large hail, damaging
winds, localized flooding, micro-bursts and tornadoes.

That's why I like California. Other than earthquakes and government, we
don't have much in the way to disasters here.

... I had just purchased a Dodge 4x4 in the spring. I was out chasing a
storm around and got pelted by some golf ball sized hail. That ended my
chasing days. I don't have a beater that I care about looking like
someone took a hammer to it.

Ouch. I've never even seen a tornado, so I have no idea what it might
be like. Raining golf balls sounds like no fun. Yes, Skywarn has its
place in your part of the country.

I urge non-hams to listen to skywarn on a scanner if they have one when
weather threatens. Anyone in Skywarn gets a text when watches/advisories
are put out by the NWS.



--
Live Fast, Die Young and Leave a Pretty Corpse

David Nebenzahl
Guest

Sat Jan 15, 2011 1:27 am   



On 1/14/2011 12:58 PM Jeff Liebermann spake thus:

Quote:
That's why I like California. Other than earthquakes and government,
we don't have much in the way to disasters here.

Hmm, tell that to all those folks who live "up the hill" from you off 17
whose houses perennially slip-slide away in the rainy season ...

But yeah, I guess apart from that, a few houses falling into the ocean
each year, and those houses that got blown up/burned up in San Bruno,
we're relatively disaster-free here.


--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

Baron
Guest

Sat Jan 15, 2011 6:43 pm   



Jeff Liebermann Inscribed thus:

Quote:
On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow
mhywatt_at_yahoo.com> wrote:

No, tapping on it will not induce micro-phonics but will often lessen
the howl.

Well, if it were "grounding", then banging on the case would have no
effect (unless there were some screws loose).

Incidentally, I tried my VX-5 turn on/off times. It took about 1
second to turn on, and the same to turn off. Pushing the button to
turn off was *NOT* instantaneous. I had to hold it for 1 sec. It's
been like that since new, so there's been no deterioration. At this
point, I don't know if it's a firmware issue, settings issue, or dirty
keyboard. Save, reset and reload seems the easiest to do first.

Once the radio is on, the howl goes away, maybe after 10 minutes.

Something is getting warm perhaps?

We have it here due to severe thunderstorms with large hail, damaging
winds, localized flooding, micro-bursts and tornadoes.

That's why I like California. Other than earthquakes and government,
we don't have much in the way to disasters here.

... I had just purchased a Dodge 4x4 in the spring. I was
out chasing a storm around and got pelted by some golf ball sized
hail. That ended my chasing days. I don't have a beater that I care
about looking like someone took a hammer to it.

Ouch. I've never even seen a tornado, so I have no idea what it might
be like. Raining golf balls sounds like no fun. Yes, Skywarn has its
place in your part of the country.


This thing doesn't have a backup battery does it ?
If so have you replaced it !

--
Best Regards:
Baron.

Jeff Liebermann
Guest

Sat Jan 15, 2011 9:33 pm   



On Fri, 14 Jan 2011 16:27:32 -0800, David Nebenzahl
<nobody_at_but.us.chickens> wrote:

Quote:
On 1/14/2011 12:58 PM Jeff Liebermann spake thus:

That's why I like California. Other than earthquakes and government,
we don't have much in the way to disasters here.

Hmm, tell that to all those folks who live "up the hill" from you off 17
whose houses perennially slip-slide away in the rainy season ...

Oh, you mean like my house?
<http://802.11junk.com/jeffl/pics/home/slides/BL-house1.html>
My guess(tm) is I'm on a 45 degree slope. However, I'm not worried
about sliding down the hill. I've gone through some effort to divert
water around the house and check for hydraulic and geological hazards.
What worries me is having one of the huge trees land on my house or
getting caught in a forest fire.

Quote:
But yeah, I guess apart from that, a few houses falling into the ocean
each year, and those houses that got blown up/burned up in San Bruno,
we're relatively disaster-free here.

Little lightning, no tornados, no hurricanes, minimal flooding, etc.
Yeah, I like it here (except for the government disasters).

--
Jeff Liebermann jeffl_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Baron
Guest

Sat Jan 15, 2011 10:13 pm   



Meat Plow Inscribed thus:

Quote:
On Sat, 15 Jan 2011 17:43:05 +0000, Baron wrote:

Jeff Liebermann Inscribed thus:

On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow
mhywatt_at_yahoo.com> wrote:

No, tapping on it will not induce micro-phonics but will often
lessen the howl.

Well, if it were "grounding", then banging on the case would have no
effect (unless there were some screws loose).

Incidentally, I tried my VX-5 turn on/off times. It took about 1
second to turn on, and the same to turn off. Pushing the button to
turn off was *NOT* instantaneous. I had to hold it for 1 sec. It's
been like that since new, so there's been no deterioration. At this
point, I don't know if it's a firmware issue, settings issue, or
dirty
keyboard. Save, reset and reload seems the easiest to do first.

Once the radio is on, the howl goes away, maybe after 10 minutes.

Something is getting warm perhaps?

We have it here due to severe thunderstorms with large hail,
damaging winds, localized flooding, micro-bursts and tornadoes.

That's why I like California. Other than earthquakes and
government, we don't have much in the way to disasters here.

... I had just purchased a Dodge 4x4 in the spring. I was out
chasing a storm around and got pelted by some golf ball sized hail.
That ended my chasing days. I don't have a beater that I care about
looking like someone took a hammer to it.

Ouch. I've never even seen a tornado, so I have no idea what it
might
be like. Raining golf balls sounds like no fun. Yes, Skywarn has
its place in your part of the country.


This thing doesn't have a backup battery does it ? If so have you
replaced it !

I think it stores in erasable prom but can't be sure. I had it open
once and don't recall seeing anything big enough to be a supercap or
battery. It's really miniaturized.


A friend of mine had a HT, Icom I think, with a 2021 battery in it. It
went bananas changing channels when you pressed TX. Turned out that
the battery was the problem. Now I don't know whether it was low
voltage or corrosion because it was repaired by the supplier.

Sadly he's now silent key, so I can't go and ask him. Come to think
about it my FT290 has a battery in it... I'll have to check that !

--
Best Regards:
Baron.

Jeff Liebermann
Guest

Sat Jan 15, 2011 10:25 pm   



On Sat, 15 Jan 2011 20:54:48 +0000 (UTC), Meat Plow
<mhywatt_at_yahoo.com> wrote:

Quote:
I think it stores in erasable prom but can't be sure. I had it open once
and don't recall seeing anything big enough to be a supercap or battery.
It's really miniaturized.

I'm too lazy to dig out the schematic, but I guess(tm) it's NVRAM of
some sort. I don't see a coin cell inside. Some inside photos:
<http://www.mods.dk/picture.php?brandid=7&model=vx-5r>
Registration required to see them full size.

Note the big white circle that is silk screen to the PCB. That's
where the speaker magnet is positioned. I suspect that if you place
some foam tape to put some pressure on the PCB, it might reduce the
microphonics.

Also, two reasons it's only on 440Mhz. It might be a seperate VCO
oscillator for each band, and the LO multiplier ratio is higher for
440 than for the other bands.

Incidentally, I sorta blundered across this BNC to SMA adapter made
specifically for various Yaesu handhelds. Looks better than the
easily broken adapters I've been using.
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350298285336>
There a bunch of others with similar design available.


--
Jeff Liebermann jeffl_at_cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Meat Plow
Guest

Sat Jan 15, 2011 10:54 pm   



On Sat, 15 Jan 2011 17:43:05 +0000, Baron wrote:

Quote:
Jeff Liebermann Inscribed thus:

On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow <mhywatt_at_yahoo.com
wrote:

No, tapping on it will not induce micro-phonics but will often lessen
the howl.

Well, if it were "grounding", then banging on the case would have no
effect (unless there were some screws loose).

Incidentally, I tried my VX-5 turn on/off times. It took about 1
second to turn on, and the same to turn off. Pushing the button to
turn off was *NOT* instantaneous. I had to hold it for 1 sec. It's
been like that since new, so there's been no deterioration. At this
point, I don't know if it's a firmware issue, settings issue, or dirty
keyboard. Save, reset and reload seems the easiest to do first.

Once the radio is on, the howl goes away, maybe after 10 minutes.

Something is getting warm perhaps?

We have it here due to severe thunderstorms with large hail, damaging
winds, localized flooding, micro-bursts and tornadoes.

That's why I like California. Other than earthquakes and government,
we don't have much in the way to disasters here.

... I had just purchased a Dodge 4x4 in the spring. I was out chasing a
storm around and got pelted by some golf ball sized hail. That ended my
chasing days. I don't have a beater that I care about looking like
someone took a hammer to it.

Ouch. I've never even seen a tornado, so I have no idea what it might
be like. Raining golf balls sounds like no fun. Yes, Skywarn has its
place in your part of the country.


This thing doesn't have a backup battery does it ? If so have you
replaced it !

I think it stores in erasable prom but can't be sure. I had it open once
and don't recall seeing anything big enough to be a supercap or battery.
It's really miniaturized.



--
Live Fast, Die Young and Leave a Pretty Corpse

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