Re: QRPGuys EFHW 40m-15m Mini Tuner
Alan
The reason for the tuner is mostly to cope with different installations. The feedpoint may be a high voltage point on the antenna, meaning it sees everything close by. This really needs to he in the clear outside.
A well adjusted efhw needs minimal counterpoise, sometimes the outside of the coax is enough. This conductor radiates also.
You can make a flat feed through section to get through the window, the use some coax inside and outside to reach a good launch point to begin radiation from the end of your antenna.
Curt
|
Re: QRPGuys EFHW 40m-15m Mini Tuner
An alternative for NVIS might be a tri-folded dipole with a reflector wire (or wires) on the ground. The spacing between driven element and ground wire(s) can be adjusted so as to match 50 ohms. I had good results with this on 40m in Central Africa. Michael 2E0IHW On 13/06/2019 23:12, Shirley Dulcey KE1L wrote: Higher isn't always better. On 40 through 80 meters, relatively low
antennas designed to have a high angle of radiation are useful for
local and regional coverage, using a propagation mode called NVIS
(Near Vertical Incidence Skywave). It's just what you want for
participation in things like traffic nets. An antenna with a low
radiation angle would be far less useful for that type of operation.
But relatively low is not all that low on the lower frequency bands.
The ideal height for an NVIS antenna is in the range of 0.2 to 0.25
wavelengths, and on 80 meters (let alone 160!) that's still pretty
high in the air. An antenna lower than 0.1 wavelengths (which is still
25 feet up on 80 meters) will be much less efficient, though heights
of 0.05 wavelengths are still usable. The heights get less daunting on
40 and 60 meters.
So i guess for most ham purposes, "higher is always better" is pretty
close to the truth. The one exception is 40 meters, where getting an
antenna up well over 0.25 wavelengths isn't that difficult to do for
people with access to trees. That operator might want to have a dipole
up at 0.5 wavelengths to get a lower radiation angle for DX, and a
second lower one for regional operation. On the higher bands it's easy
to get a dipole up higher than the best height for DX, but most people
with the ability to do that will be putting up directional beam
antennas instead. --- Diese E-Mail wurde von Avast Antivirus-Software auf Viren gepr¨¹ft.
|
Re: QRPGuys EFHW 40m-15m Mini Tuner
Higher isn't always better. On 40 through 80 meters, relatively low
antennas designed to have a high angle of radiation are useful for
local and regional coverage, using a propagation mode called NVIS
(Near Vertical Incidence Skywave). It's just what you want for
participation in things like traffic nets. An antenna with a low
radiation angle would be far less useful for that type of operation.
But relatively low is not all that low on the lower frequency bands.
The ideal height for an NVIS antenna is in the range of 0.2 to 0.25
wavelengths, and on 80 meters (let alone 160!) that's still pretty
high in the air. An antenna lower than 0.1 wavelengths (which is still
25 feet up on 80 meters) will be much less efficient, though heights
of 0.05 wavelengths are still usable. The heights get less daunting on
40 and 60 meters.
So i guess for most ham purposes, "higher is always better" is pretty
close to the truth. The one exception is 40 meters, where getting an
antenna up well over 0.25 wavelengths isn't that difficult to do for
people with access to trees. That operator might want to have a dipole
up at 0.5 wavelengths to get a lower radiation angle for DX, and a
second lower one for regional operation. On the higher bands it's easy
to get a dipole up higher than the best height for DX, but most people
with the ability to do that will be putting up directional beam
antennas instead.
toggle quoted message
Show quoted text
On Thu, Jun 13, 2019 at 4:15 PM ajparent1/kb1gmx <kb1gmx@...> wrote:
For antenna in general the radiating portion is beat further form the shack as
possible for RFI reasons (if in the mic and RF from stuff int he house).
However at lower power (qrp) there is a more latitude and generally fewer
issues with RFI in the mic issues. Noise formt eh house may still be an issue.
Counterpoise, outside is likely better but it may may little difference, try
it both ways and see.
The radiating portion of a EFHW wire should be fully in the open
and away from metallic items. Many homes have foil covered
instulation and those area should be giving the most distance.
Straight or less than a 90 degree bends are ok but may required
the wire length to be adjusted.
FYI Higher is always better. HOwever before fretting try it see
what it does then consider possible improvements for
convenience or height.
Allison
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Re: QRPGuys EFHW 40m-15m Mini Tuner
For antenna in general the radiating portion is beat further form the shack as
possible for RFI reasons (if in the mic and RF from stuff int he house).
However at lower power (qrp) there is a more latitude and generally fewer
issues with RFI in the mic issues. Noise formt eh house may still be an issue.
Counterpoise, outside is likely better but it may may little difference, try
it both ways and see.
The radiating portion of a EFHW wire should be fully in the open
and away from metallic items. Many homes have foil covered
instulation and those area should be giving the most distance.
Straight or less than a 90 degree bends are ok but may required
the wire length to be adjusted.
FYI Higher is always better. HOwever before fretting try it see
what it does then consider possible improvements for
convenience or height.
Allison
|
QRPGuys EFHW 40m-15m Mini Tuner
Yesterday I installed my EFHW 40m-15m Mini Tuner in the shack close to my window. The distance from my window to the Mini Tuner is about 30 inches. The tuner is mounted so that I can easily tune it from my operating position. The active wire, cut for 40 meters, goes out my window through a wood feed through, slopes up to top of a mast pipe through a plastic feeder hole, then slopes down about one foot over my garage roof and continues out into a backyard tree. I still haven't hooked up a counterpoise yet. Is it ok to lay the counterpoise on the shack floor or should I get it outside. The small patch of yard outside my window is only about 13 x 9 x 6 triangle between my shack and the garage.
I was wondering if anyone else uses the tuning portion of an EFHW antenna in the shack, what kind of success you've had and/or lack of, and how you installed your counterpoise.
Alan, N8WQ
|
Re: Universal receiver kit 40m
The receiver is identical to the one use in the 1W transceiver. I have several
of those and they are very good.
The biggest issue is its a very tight build and great care is needed
to insure wall the parts are in the right place an the coils are correctly
wound and soldered.
Allison
|
Universal receiver kit 40m
Hello homebrewers,
I am building a universal receiver kit from partsandkits.com for the 40m band. I followed the sequence in your Chuck's excellent video series - started from the audio amp and up from there. At this point, I have the VFO soldered up. I can hear the distinct narrow band CW sound. However I can't hear any stations when I hook up an antenna. I have a Elecraft XG1 50uV signal generator that generates a tone at 7040. But no, I can't hear that too.
So, I acquired a frequency counter from aliexpress. PIC based with a good LCD display, meant for rig displays I guess, but I am using it as a measurement tool.. The VFO is generated out of the SA602AN's pin 6 and 7 in a colpitts configuration. On the website, I couldn't find any values for the actual VFO output or the inductance, but I calculated the frequency as follows.
Center frequency of the crystal filter is 5067400 Hz. We would want our input RF to be shifted down to this intermediate frequency by the VFO. Input RF is from 7006000 to 7079000.
So, VFO range should be from 7006000 - 5067400 = 1938600 to 7079000 - 5067400 = 2011600.
When I look at the VFO output, with the potentiometer from one end to another, it is going from 1929000 to 2000000. So, the input RF I am tuning is 5067400 + 1929000 = 6996400 to 5067400 + 2000000 = 7067400. 7040000 falls well within this band, but it didn't appear when I tuned the VFO. I am unable to explain why that is the case.
I found a couple of wrongly soldered capacitor values around the VFO, but I think those are not too important ones. From my reading of the circuit, C6 and C8 and L2 are the ones that determine the VFO frequency. I am guessing that the variation in my VFO frequency is because of the inductance difference, probably because of the way I wired up the toroid. The one I have wrongly soldered are these:
Wrongly populated C9 with 180pf.
C10 is not populated.
C11 has a 470pf one instead of 180pf.
I will fix these and check again.
Universal Receiver circuit: <>
Has anyone else tried this little receiver? I really liked the simplicity of the receiver and want to figure out what is going on, but I don't have an oscilloscope or any other fancy test equipment. Any help/ideas/directions appreciated.
73
--
Ramakrishnan VU3RDD
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
Sincere thanks to all for both the technical advice AND the wit! Sad to say that the battery is dead..
..long live the [new] battery.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
[image: He's dead, Jim.jpg]
toggle quoted message
Show quoted text
On Sun, Jun 9, 2019 at 1:36 PM Randy.AB9GO <randy.ab9go@...> wrote: I've worked with UPS batteries for years professionally. Short and sweet.
From your description it is dead. Don't waste any more time on it. It's
not coming back.
Randy AB9GO.
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
I've worked with UPS batteries for years professionally. Short and sweet.
From your description it is dead. Don't waste any more time on it. It's
not coming back.
Randy AB9GO.
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
Hi,
I haven't read quite all of the other replies. I have worked with a lot of lead-acid batteries over a lot of years and I even have the lab notes. If you have access to the cells through a water fill port on top of each cell you might make sure the cells are all flloded. Then take hydrometer readings to measure the specific gravity. If you top off the cells and charge the battery at a much lower rate - I used 100 milliamps in my 'recovery room - and maybe for a couple of weeks you might recover the battery. Monitor the specific gravity periodically and record it for each cell. Statistically, you should just cut your losses and trade it in on a new battery. You are very unlikely to recover the battery. The other replies are almost perfect.
A few years ago I had a spectacular success with a battery that had been laying in the back of a pickuo truck for a whole summer. It was just flat-out *dead*. The young owner needed a battery as the one operating his old truck was failing. It took six weeks to recover that old dead thing. I did it for the lab experiment value. The young man then used it for more than a year including cold Michigan winters. That is the example that highlights the rarity of such successes. Any other battery with initial readings like yours were just so much scrap and went to the recyclers.
FD will be here well before you can recover that battery even if you can recover it. Treat the new battery more kindly that you did this one. Automotive batteries have a different physical structure intended to provide very high momentary currents and take very high momentary recharging. Deep-cycle batteries will roll over and die on you if treated that way.
Have fun at FD with your new battery.
73,
Bill KU8H
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On 6/8/19 7:29 PM, k6whp wrote: Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and wondring if it's met its maker. Ostensibly in good condition (so sayeth the donor), it's been on an automobile battery charger for three days drawing about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger" or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
--
bark less - wag more
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
Can you remove some electrolyte, replce with distilled eater and do
desulphation process. Shold restore your bteery in around three days.
Ifinternal treeing ( shorting between plates) is there perhaps we cant help
much.
All the best
Sarma vu3zmv
toggle quoted message
Show quoted text
On Sun, 9 Jun 2019, 4:59 am k6whp <k6whp@... wrote: Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and
wondring if it's met its maker. Ostensibly in good condition (so sayeth the
donor), it's been on an automobile battery charger for three days drawing
about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger" or
"revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough,
things got worse!"
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
A couple of suggestions from my experience. Check the water level. You
can purchase a battery revitalize liquid that might help. I found it at an
automotive parts center.
I had a battery, after I added water, that I recharged at a higher current
for about 30 seconds. The water boiled a bit and then charged it starting
at 10 amps with a diminishing charge (special charger). I was able to
bring it back to life.
However, if the cells are internally shorted or the chemistry is not good
there is not a lot you can do. Use it as a core to reduce the cost of a
new battery.
Larry - N7RGW
toggle quoted message
Show quoted text
On Sat, Jun 8, 2019 at 8:02 PM David Lininger <kb0zke@...> wrote: If it were my battery I'd be replacing it. I don't have a lot of
patience with trying to bring batteries back to life. That said, if said
battery belongs to my employer I'll do what I can to help it.
We worked as campground hosts at a State park. We were issued a handheld
radio, but were told that it didn't seem to hold a charge. I put it on
the charger, and watched the light. After several hours it still wasn't
indicating a charge. It did work for an hour or so, though. After a week
of charging overnight and whenever I could during the day I finally got
it to where it would hold a charge all day, even with several calls. I
did suggest to the ranger in charge that he probably ought to be
budgeting for some new batteries, if not new radios.
On 8/6/19 20:38, Alan de G1FXB via Groups.Io wrote:
Sorry for apparent brevity, but I'll try to provide the background
picture, If short of time fast forward to he final paragraph?
(Coming from a marine environment perspective,
Assuming conventional wet Lead / Acid chemistry or one of simple cousins.)
The Deep cycle description is not an invitation that it will survive
repeated deep discharge, without *severe* service life penalty.
Usable capacity is generally considered 30% of AH capacity, If a battery
advertised as 100AH, then real life is you will be able to draw 30A for
an Hour.
/May not meet with universal approval...
If a manufacture specifies 1A for 30 Hours then that's not the same, and
perhaps questions confidence of their figures for a deep discharge
battery./
In probability it will last +5-7 years if kept above 50% state of charge
in short term, store as close to 100% charge as possible
which is where the modern automated maintenance chargers excel.
Some will last +10 years and don't have to be premium brands, just how
good their owners charge / discharge and cell maintenance was.
(yes the sweet spot between 80 - 50% charge they rarely get the chance
to top off above 80% SOC in real (marine) service.
Discharge below 50% and how ever fancy the miracle cure is promised be
it Magic tablets to drop in the cells or automated reverse
de-sulphaters" they don't recover.
Many batteries even if advertised as "Sealed for Life" have old
fashioned removable cell caps hidden beneath a lid.
Often disguised and hard to remove for sealed for life,
alternatively less hard types to remove and advertised as "Low Maintenance"
Regular good maintenance never killed a battery, a battery advertising
requires maintenance is a positive selling point in my book, so long as
you do.
It's also a good guide to it's health, if one cell begins to require
topping up, you know perhaps it's not long for this world....
3 days at 5-6A charge current and only reaches 9V.
Firstly charge outside & don't smoke or make sparks....
Assuming you are using an old skool auto charger, simple rectified but
unsmoothed DC & desirable in this situation but needs manual over-seeing.
Electrical energy is going in and being absorbed somewhere, does the
battery feel hot along the body at any point?
One or more cells gassing but not others?
Manufactures will stamp the production date on the battery, they have to
know it for dealing with warranty claims.
It will be there in some form, maybe disguised, google will be your friend.
How hard do you want to try to recover it, there are not many "repair"
options. Perhaps only one.
Drain cells and dispose of acid and any sediment responsibly, flush
cells with running water to best "try" to remove dead plate material,
replace with correct SG acid / water mix
and charge.
In all honesty, it sounds the value is in it's scrap lead content. To
which there is some, perhaps not as a single battery but 5 / 10
depending on recycle centre.
what capacity do you expect in return? It will not be back as advertised
and that may be far from what you had originally expected
There is no such thing as a cheap battery, "best value" for deep
discharge use are perhaps traction batteries for golf carts etc or solar.
Get a price for a similar specification Marine battery for comparison.
Say to the vendor its for marine use and they think you have cruseliner
sized wallet, at least in the UK....
Alan
On 09/06/2019 00:29, k6whp wrote:
Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and
wondring if it's met its maker. Ostensibly in good condition (so
sayeth the donor), it's been on an automobile battery charger for
three days drawing about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger"
or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
--
David Lininger, kb0zke
Rev. 2:10
kb0zke@...
--
Larry Lovell
73's N7RGW
<>
Cell: 214-697-1729
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
If it were my battery I'd be replacing it. I don't have a lot of
patience with trying to bring batteries back to life. That said, if said
battery belongs to my employer I'll do what I can to help it.
We worked as campground hosts at a State park. We were issued a handheld
radio, but were told that it didn't seem to hold a charge. I put it on
the charger, and watched the light. After several hours it still wasn't
indicating a charge. It did work for an hour or so, though. After a week
of charging overnight and whenever I could during the day I finally got
it to where it would hold a charge all day, even with several calls. I
did suggest to the ranger in charge that he probably ought to be
budgeting for some new batteries, if not new radios.
toggle quoted message
Show quoted text
On 8/6/19 20:38, Alan de G1FXB via Groups.Io wrote: Sorry for apparent brevity, but I'll try to provide the background
picture, If short of time fast forward to he final paragraph?
(Coming from a marine environment perspective,
Assuming conventional wet Lead / Acid chemistry or one of simple cousins.)
The Deep cycle description is not an invitation that it will survive
repeated deep discharge, without *severe* service life penalty.
Usable capacity is generally considered 30% of AH capacity, If a battery
advertised as 100AH, then real life is you will be able to draw 30A for
an Hour.
/May not meet with universal approval...
If a manufacture specifies 1A for 30 Hours then that's not the same, and
perhaps questions confidence of their figures for a deep discharge
battery./
In probability it will last +5-7 years if kept above 50% state of charge
in short term, store as close to 100% charge as possible
which is where the modern automated maintenance chargers excel.
Some will last +10 years and don't have to be premium brands, just how
good their owners charge / discharge and cell maintenance was.
(yes the sweet spot between 80 - 50% charge they rarely get the chance
to top off above 80% SOC in real (marine) service.
Discharge below 50% and how ever fancy the miracle cure is promised be
it Magic tablets to drop in the cells or automated reverse
de-sulphaters" they don't recover.
Many batteries even if advertised as "Sealed for Life" have old
fashioned removable cell caps hidden beneath a lid.
Often disguised and hard to remove for sealed for life,
alternatively less hard types to remove and advertised as "Low Maintenance"
Regular good maintenance never killed a battery, a battery advertising
requires maintenance is a positive selling point in my book, so long as
you do.
It's also a good guide to it's health, if one cell begins to require
topping up, you know perhaps it's not long for this world....
3 days at 5-6A charge current and only reaches 9V.
Firstly charge outside & don't smoke or make sparks....
Assuming you are using an old skool auto charger, simple rectified but
unsmoothed DC & desirable in this situation but needs manual over-seeing.
Electrical energy is going in and being absorbed somewhere, does the
battery feel hot along the body at any point?
One or more cells gassing but not others?
Manufactures will stamp the production date on the battery, they have to
know it for dealing with warranty claims.
It will be there in some form, maybe disguised, google will be your friend.
How hard do you want to try to recover it, there are not many "repair"
options. Perhaps only one.
Drain cells and dispose of acid and any sediment responsibly, flush
cells with running water to best "try" to remove dead plate material,
replace with correct SG acid / water mix
and charge.
In all honesty, it sounds the value is in it's scrap lead content. To
which there is some, perhaps not as a single battery but 5 / 10
depending on recycle centre.
what capacity do you expect in return? It will not be back as advertised
and that may be far from what you had originally expected
There is no such thing as a cheap battery, "best value" for deep
discharge use are perhaps traction batteries for golf carts etc or solar.
Get a price for a similar specification Marine battery for comparison.
Say to the vendor its for marine use and they think you have cruseliner
sized wallet, at least in the UK....
Alan
On 09/06/2019 00:29, k6whp wrote:
Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and
wondring if it's met its maker. Ostensibly in good condition (so
sayeth the donor), it's been on an automobile battery charger for
three days drawing about 5-6 amps? with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger"
or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
--
David Lininger, kb0zke
Rev. 2:10
kb0zke@...
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
Sorry for apparent brevity, but I'll try to provide the background picture, If short of time fast forward to he final paragraph?
(Coming from a marine environment perspective,
Assuming conventional wet Lead / Acid chemistry or one of simple cousins.)
The Deep cycle description is not an invitation that it will survive repeated deep discharge, without *severe* service life penalty.
Usable capacity is generally considered 30% of AH capacity, If a battery advertised as 100AH, then real life is you will be able to draw 30A for an Hour.
/May not meet with universal approval...
If a manufacture specifies 1A for 30 Hours then that's not the same, and perhaps questions confidence of their figures for a deep discharge battery./
In probability it will last +5-7 years if kept above 50% state of charge in short term, store as close to 100% charge as possible
which is where the modern automated maintenance chargers excel.
Some will last +10 years and don't have to be premium brands, just how good their owners charge / discharge and cell maintenance was.
(yes the sweet spot between 80 - 50% charge they rarely get the chance to top off above 80% SOC in real (marine) service.
Discharge below 50% and how ever fancy the miracle cure is promised be it Magic tablets to drop in the cells or automated reverse de-sulphaters" they don't recover.
Many batteries even if advertised as "Sealed for Life" have old fashioned removable cell caps hidden beneath a lid.
Often disguised and hard to remove for sealed for life,
alternatively less hard types to remove and advertised as "Low Maintenance"
Regular good maintenance never killed a battery, a battery advertising requires maintenance is a positive selling point in my book, so long as you do.
It's also a good guide to it's health, if one cell begins to require topping up, you know perhaps it's not long for this world....
3 days at 5-6A charge current and only reaches 9V.
Firstly charge outside & don't smoke or make sparks....
Assuming you are using an old skool auto charger, simple rectified but unsmoothed DC & desirable in this situation but needs manual over-seeing.
Electrical energy is going in and being absorbed somewhere, does the battery feel hot along the body at any point?
One or more cells gassing but not others?
Manufactures will stamp the production date on the battery, they have to know it for dealing with warranty claims.
It will be there in some form, maybe disguised, google will be your friend.
How hard do you want to try to recover it, there are not many "repair" options. Perhaps only one.
Drain cells and dispose of acid and any sediment responsibly, flush cells with running water to best "try" to remove dead plate material, replace with correct SG acid / water mix
and charge.
In all honesty, it sounds the value is in it's scrap lead content. To which there is some, perhaps not as a single battery but 5 / 10 depending on recycle centre.
what capacity do you expect in return? It will not be back as advertised and that may be far from what you had originally expected
There is no such thing as a cheap battery, "best value" for deep discharge use are perhaps traction batteries for golf carts etc or solar.
Get a price for a similar specification Marine battery for comparison.
Say to the vendor its for marine use and they think you have cruseliner sized wallet, at least in the UK....
Alan
toggle quoted message
Show quoted text
On 09/06/2019 00:29, k6whp wrote: Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and wondring if it's met its maker. Ostensibly in good condition (so sayeth the donor), it's been on an automobile battery charger for three days drawing about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger" or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
I used a deep cycle battery for a couple of years that my son was able to get for me from where he worked at the time ( Batteries Plus ) that no longer had the oomph to start a car, but held a charged fine. It never took more than 12 hours to charge when I drained it too low but usually much less.
Once, the charger had been changed to the six volt setting without my realizing it and the battery would not charge until I set it back to 12 volts.
toggle quoted message
Show quoted text
On Jun 8, 2019 at 20:15, <NT0Z via Groups.Io Kirk (mailto:sohosources@...)> wrote:
Search online for coupon codes for Advance Auto (worth $20 - $50 bux).
Buy battery online and choose to pick it up at your local store.
Use dead battery as "core" trade in.
Best price so far in my neck of the woods.
Good luck,
--Kirk, NT0Z My book, "Stealth Amateur Radio," is now available from www.stealthamateur.com and on the Amazon Kindle (soon)
On Saturday, June 8, 2019 8:12 PM, k6whp <k6whp@...> wrote:
..think we're talking elephant graveyard here, right?
Time to see what a trade-in gets me at O'Reilly.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
"k6whp" <k6whp@...> writes: Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and
wondring if it's met its maker. Ostensibly in good condition (so
sayeth the donor), it's been on an automobile battery charger for
three days drawing about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger" or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days? A 12V battery has 6 cells with a nominal float voltage of 2.3V/cell on float, for 13.8V. It will soonish draw very little current if maintained at 13.8V, and then on being disconnected fall to 12.9V ish. 5-6A is way more than float (you didn't say what capacity, but if it's 30 Ah to 120 Ah, float current should be from 30 mA to 240 mA (assuming C/500h to C/1000h)). That's ok for a few hours initially if discharged and healthy, but it should soon settle down to < 1A. And, 9V on charge is basically never ok - a fully discharged battery should be at 11.4V open circuit, or maybe 10.5V if very stressed, and rise rapidly on charge. 9V sounds like 3 or 4 cells are ok (and being grossly overcharged), with two or maybe three cells shorted. I'd take if off charge and let it sit 24h and measure it. If it is at 12.9, maybe it's ok, but if under 12V, it sounds like the battery is quite damaged. 73 de n1dam
|
Re: Charging a Deep-Cycle Marine Battery; Is it dead?
Search online for coupon codes for Advance Auto (worth $20 - $50 bux).
Buy battery online and choose to pick it up at your local store.
Use dead battery as "core" trade in.
Best price so far in my neck of the woods.
Good luck,
--Kirk, NT0Z?My book, "Stealth Amateur Radio," is now available from www.stealthamateur.com and on the Amazon Kindle (soon)
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On Saturday, June 8, 2019 8:12 PM, k6whp <k6whp@...> wrote:
..think we're talking elephant graveyard here, right?
Time to see what a trade-in gets me at O'Reilly.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
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Re: Charging a Deep-Cycle Marine Battery; Is it dead?
..think we're talking elephant graveyard here, right?
Time to see what a trade-in gets me at O'Reilly.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"
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Re: Charging a Deep-Cycle Marine Battery; Is it dead?
I'm not a real authority on lead acid batteries, ....but if you put 6 amps into one for three days continuous, ...I'd? be on the front pew in church in the morning.
Don?? N5CID
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On 6/8/2019 6:29 PM, k6whp wrote: Gents,
In advance of FD, I "inherited" a deep-cycle marine/RV battery and wondring if it's met its maker. Ostensibly in good condition (so sayeth the donor), it's been on an automobile battery charger for three days drawing about 5-6 amps with a terminal voltage of 9 volts.
I did the research but a lot of the info is "buy our miracle charger" or "revitalize your dead batteries with our wonder product", etc.
Any verdict on this; a few more days?
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Shirley Dulcey KE1L
Alan N8WQ
Ramakrishnan Muthukrishnan (VU3RDD)
Randy.AB9GO
Larry Lovell
Alan de G1FXB
Kirk, NT0Z