K2 Battery Charging System With out Mods?
Locked
K2 Battery Charging System With out Mods?
 
|
Hello all,
Is there a simple off the shelf model of battery charger which I can buy or build that will properly charge the K2 battery? I'd prefer not to drill a hole in the rear apron, so I'm looking for a commercial solution, ideally with an adjustable output. What have you found that works, or how did you solve your K2 battery dilemma? Thanks! 73 Bruce W1UJR www.w1ujr.net _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K2 Battery Charging System With out Mods?
|
|
Bruce,
The answer is yes. There are several choices, but here are two basic ones. 1) Use a power supply that you can adjust upward to the 13.1 to 14.3 volt range to power the K2. The internal battery will charge, but it will take a long time to come to a full capacity charge. 2) Make a direct connection to the battery and use a 2 or 3 state charger designed specifically for charging gel cells. The A&A Smartcharger is one example. You do not have to drill any holes - use the existing transverter holes in the top cover to mount the jack for the direct battery connection. Be sure to put a fuse inside the K2 when making the direct battery connection, if the external connection is shorted in any way, one would find out just how much energy is in a gel cell - molten metal, flying bits of hot conductor pieces, and other bad things will happen. Even though the voltage is low, it is still dangerous because the current capacity is huge. See my website www.w3fpr.com for information related to 2) above. 73, Don W3FPR Bruce James Howes wrote: > Hello all, > > Is there a simple off the shelf model of battery charger which I can > buy or build that will properly charge the K2 battery? > I'd prefer not to drill a hole in the rear apron, so I'm looking for a > commercial solution, ideally with an adjustable output. > > What have you found that works, or how did you solve your K2 battery > dilemma? > > Thanks! > > > 73 Bruce W1UJR > www.w1ujr.net > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
In reply to this post by Bruce W1UJR
Hi Bruce,
I do not have the battery pack in my K2 however for years I have been using these chargers for various Gel cells and small lead acid batteries: http://batterytender.com/selection_guide.php The Plus model at $60 is a 4 step charger for gel cells, and others, and the JR at $40 is a 3 step charger that I have used also on very small Gel cell batteries when a lower charge rate was desired. These are very popular in the Motorcycle world. They are discounted quite a bit and I've seen them for $35 and $27 each. When the MC's are retired for the winter I just leave a charger connected and they are ready to go in the spring. I have 3 Plus models and a JR and they have never failed me. No financial interest just a satisfied customer. 73, Bob K2TK Bruce James Howes wrote: > Hello all, > > Is there a simple off the shelf model of battery charger which I can > buy or build that will properly charge the K2 battery? > I'd prefer not to drill a hole in the rear apron, so I'm looking for > a commercial solution, ideally with an adjustable output. > > What have you found that works, or how did you solve your K2 battery > dilemma? > > Thanks! > > > 73 Bruce W1UJR > www.w1ujr.net > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K2 Battery Charging System With out Mods?
Administrator
|
I have used the Battery Tender as well, the smaller one for the K2 and a larger one for external batteries. You can't use the existing K2 power jack to charge unless you remove some components, as because of the voltage drop, the smart charger will be outwitted and overcharge the battery. So, at least some modification is necessary, and if you leave the resistor in place, your K2 will be consistent with others and can properly handle the 14v slow charge through its DC jack. I believe drilling the hole is the best solution, because it adds a second jack explicitly for charging. I saw Wayne N6KR's K2 and he had mounted an extra plug or two in the back of his K2 as well (though his was for DC out), through one of the old transverter holes. So I think it's A-OK, kinda like replacing the RCA phono jack that Heathkit used to use for antenna connections with an SO-239. Here's how I did it: http://wa5znu.org/log/2005/01/k2-charging-jack.html Since I did it, Unibits have come down in price, and inexpensive competitors from Harbor Freight and Northern Tool are available. I found that I had to stop just shy of the battery to get the hole the right size. Originally I planned to replace the K2 power switch with a double-pole double-throw switch to allow me to have the charging jack active or the battery connected, but not both; however, I eventually decided not to do this and just hook the charging jack up through an internal fuse as Don recommended. I used a mini-blade fuse internally in the plus line, and ran a separate minus line. I do notice some hum if the charger is on red; this could mean my battery is getting old, or it could happen to everyone (although Don hasn't reported it is an issue for him). Having the charger jack also means you can use a Northern Tool 350ma folding solar panel and replenish the battery in the K2 while it's operating! I don't have the Radio Shack part number for the jack I used, but you can see it in the 4th picture. I believe they have a couple of sizes; it's up to you whether you want to use the same as the K2 power plug, or use a different size to more clearly separate them. Leigh/WA5ZNU On Fri, 26 Sep 2008 14:17:28 -0400, Bob <[hidden email]> wrote: > Hi Bruce, > > I do not have the battery pack in my K2 however for years > I have been using these chargers for various > Gel cells and small lead acid batteries: > > http://batterytender.com/selection_guide.php > > The Plus model at $60 is a 4 step charger for gel cells, > and others, and the JR at $40 is a 3 step charger > that I have used also on very small Gel cell batteries when a lower > charge rate was desired. > > These are very popular in the Motorcycle world. They > are discounted quite a bit and I've seen them > for $35 and $27 each. When the MC's are retired for the winter I just > leave a charger connected and they are > ready to go in the spring. I have 3 Plus models and a JR and they have > never failed me. > > No financial interest just a satisfied customer. > > 73, > Bob > K2TK > > > Bruce James Howes wrote: > >> Hello all, >> >> Is there a simple off the shelf model of battery charger which I can >> buy or build that will properly charge the K2 battery? >> I'd prefer not to drill a hole in the rear apron, so I'm looking for >> a commercial solution, ideally with an adjustable output. >> >> What have you found that works, or how did you solve your K2 battery >> dilemma? >> >> Thanks! >> >> >> 73 Bruce W1UJR >> www.w1ujr.net >> > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
In reply to this post by Don Wilhelm-4
I use Don's system described below in #2) with the A&A charger and recommend it. It keeps the K2's battery healthy, and I also use it for other gel-cell batteries around the shack. Plus, when out in the field, the added power jack on the back of tyhe K2 makes a convenient spot to connect an analog expanded-scale DC voltmeter to monitor the state of charge (even though the K2 can also monitor its own voltage). The meter I use is a Zantum Technologies model ZAPV15 "12 Volt Lead Acid Battery Capacity Charge Meter" with a nice multi-colored scale.
73, John W2XS 2) Make a direct connection to the battery and use a 2 or 3 state charger designed specifically for charging gel cells. The A&A Smartcharger is one example. See my website www.w3fpr.com for information related to 2) above. |
Re: K2 Battery Charging System With out Mods?
|
|
Hi John and all,
For us more casual users of a charger does anyone know of site that might have a schematic for a homebrew charger that accomplishes the same things as is being discussed here? The A&A charger looks like it runs about $70, which is a fair price, but basically I'm a cheapskate :) . Thanks Tom WB2QDG K2# 1103 ----- Original Message ----- From: "John W2XS" <[hidden email]> To: <[hidden email]> Sent: Friday, September 26, 2008 9:17 PM Subject: Re: [Elecraft] K2 Battery Charging System With out Mods? > > I use Don's system described below in #2) with the A&A charger and > recommend > it. It keeps the K2's battery healthy, and I also use it for other > gel-cell > batteries around the shack. Plus, when out in the field, the added power > jack on the back of tyhe K2 makes a convenient spot to connect an analog > expanded-scale DC voltmeter to monitor the state of charge (even though > the > K2 can also monitor its own voltage). The meter I use is a Zantum > Technologies model ZAPV15 "12 Volt Lead Acid Battery Capacity Charge > Meter" > with a nice multi-colored scale. > > 73, John W2XS > > 2) Make a direct connection to the battery and use a 2 or 3 state charger > designed specifically for charging gel cells. The A&A Smartcharger is one > example. See my website www.w3fpr.com for information related to 2) > above. > > > > > -- > View this message in context: > http://n2.nabble.com/K2-Battery-Charging-System-With-out-Mods--tp1120435p1122331.html > Sent from the Elecraft mailing list archive at Nabble.com. > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K2 Battery Charging System With out Mods?
|
|
Tom,
The charger that the A & A Engineering Smartcharger is based on appears in my 1994 ARRL Handbook at 27-16. It claims to be an update from the original article by Warren Dion N1BBH which appeared in June 1987 QST. It uses the Unitrode UC3906/UC2906 charge controller. 73, Don W3FPR Tom McCulloch wrote: > Hi John and all, > > For us more casual users of a charger does anyone know of site that > might have a schematic for a homebrew charger that accomplishes the > same things as is being discussed here? > > The A&A charger looks like it runs about $70, which is a fair price, > but basically I'm a cheapskate :) . > > Thanks > Tom > WB2QDG > K2# 1103 > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: K2 Battery Charging System With out Mods?
|
|
In reply to this post by Tom McCulloch
In a recent message, Tom McCulloch <[hidden email]> wrote ...
> For us more casual users of a charger does anyone know of site that >might have a schematic for a homebrew charger that accomplishes the >same things as is being discussed here? I can thoroughly recommend the SLA smart charger described in the May 2001 issue of QST by Bob Lewis AA4PB. It is designed specifically for the K2 and enables the charger to be connected at all times when the K2 is in operation. I use one and my K2 SLA battery lasted for eight years before giving up the ghost. 73 -- David G4DMP Leeds, England, UK ------ _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
In reply to this post by Tom McCulloch
Hi,
I have not checked current availability but Far Circuits had the ARRL handbook version PCB available. It was basically the same as the A&A design and even they sold their PCB in the past. 73, Bob K2TK Tom McCulloch wrote: > Hi John and all, > > For us more casual users of a charger does anyone know of site that > might have a schematic for a homebrew charger that accomplishes the > same things as is being discussed here? > > The A&A charger looks like it runs about $70, which is a fair price, > but basically I'm a cheapskate :) . > > Thanks > Tom > WB2QDG > K2# 1103 > > > ----- Original Message ----- From: "John W2XS" <[hidden email]> > To: <[hidden email]> > Sent: Friday, September 26, 2008 9:17 PM > Subject: Re: [Elecraft] K2 Battery Charging System With out Mods? > > >> >> I use Don's system described below in #2) with the A&A charger and >> recommend >> it. It keeps the K2's battery healthy, and I also use it for other >> gel-cell >> batteries around the shack. Plus, when out in the field, the added power >> jack on the back of tyhe K2 makes a convenient spot to connect an analog >> expanded-scale DC voltmeter to monitor the state of charge (even >> though the >> K2 can also monitor its own voltage). The meter I use is a Zantum >> Technologies model ZAPV15 "12 Volt Lead Acid Battery Capacity Charge >> Meter" >> with a nice multi-colored scale. >> >> 73, John W2XS >> >> 2) Make a direct connection to the battery and use a 2 or 3 state >> charger >> designed specifically for charging gel cells. The A&A Smartcharger >> is one >> example. See my website www.w3fpr.com for information related to 2) >> above. >> >> >> >> >> -- >> View this message in context: >> http://n2.nabble.com/K2-Battery-Charging-System-With-out-Mods--tp1120435p1122331.html >> >> Sent from the Elecraft mailing list archive at Nabble.com. >> >> _______________________________________________ >> Elecraft mailing list >> Post to: [hidden email] >> You must be a subscriber to post to the list. >> Subscriber Info (Addr. Change, sub, unsub etc.): >> http://mailman.qth.net/mailman/listinfo/elecraft >> >> Help: http://mailman.qth.net/subscribers.htm >> Elecraft web page: http://www.elecraft.com > > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
|
|
In reply to this post by Bruce W1UJR
Hi, Bruce:
We can go to great lengths looking for technological perfection. There are all kinds of schemes to charge the internal battery of the K2 in "optimal" ways, as illustrated to the responses to your post. After going through the same thoughts you are going through I resorted back to the simple solution: Adjusted the output voltage of my 12V bench supply to 14.2V and kept my K2 hooked up to this in my shack. This ensures that the internal battery will be at a reasonably high voltage when I unplug the rig and take it along on a trip. The energy supply may not be maximized, and the lifetime of the battery may not end up being optimal either, but if the battery will serve me well in this way for some 3-5 years I won't complain. Perhaps I will try some more efficient / lighter battery technology at that time. So far this has worked perfectly and the internal gel cell battery has kept my K2 running for a total of 15-25 hours, on trips lasting weeks. 73 - Kristinn, TF3KX
|
«
Return to Elecraft
|
1 view|%1 views
| Free forum by Nabble | Edit this page |