++++++++++++++++++++++++++++++ Date: Sun, 18 Mar 2001 00:22:54 -0700 From: "David Gilbert" Subject: [Elecraft] Lighted Display for K1 I've played around with a couple of different schemes for lighting my K1's display and finally found one I like, so I thought I'd pass it on. I used a pair of "ultrabright" white LEDs from All Electronics (I think it is their part number LED-48, and they cost roughly $3 each) in series with each other and with a 1200 ohm resistor. I used a small piece of perf board to position them to the right and left of the display, and they point at an angle toward the display but also to the back side of the front panel ... away from the face of the display. To reflect the light back onto the display, I used a piece of adhesive backed aluminum foil that I got from Home Depot as a roll of aluminum tape. I cut the foil about 3/8 inch larger than the display on all sides, and I just trimmed out the display window with a razor blade after sticking the foil down on the inside face of the front panel. The fit for the LEDs is slightly snug, but I filed down the face of the LEDs just a bit for a little extra room, and that gave some extra diffusing effect that also helps. I tacked the perf board down just below the LCD display with a little dab of heat glue. Like others who have made similar lighting modifications, I picked up 12 volts off the front panel edge connector (pin 16 for +12v, pin 20 for ground). The LEDs reflecting off the foil give a bright halo effect around the entire display, and they only draw an extra 5 ma from the battery. 73, Dave AB7E K1 #412 ++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 18 Mar 2001 06:00:48 -0800 From: Phil Wheeler Subject: Re: [Elecraft] Lighted Display for K1 My "mod" was to use a little tri-LED headlamp. I can also read my log, etc. with it. Phil W7OX ++++++++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 18 Mar 2001 07:44:47 -0700 From: "David Gilbert" Subject: Re: [Elecraft] Lighted Display for K1 Hi, Phil. Yeah, curiously enough, I've been planning to do the same for camping/backpacking trips. I even slapped a preliminary one together using a battery holder for 4 AA cells. I wanted it to perform the same for both Alkaline cells (4x1.5v = 6v) or NiMH (4x1.2v = 4.8v), so I used an MPF102 JFET with the source/gate connected to make a current limiter instead of a resistor. The prototype gave me about 6 ma all the way up to 12v. Amazing how bright these LEDs are ... 73, Dave AB7E K1 #412 ++++++++++++++++++++++++++++++++++++++++++++++ Date: Sat, 24 Mar 2001 09:16:32 -0700 From: "David Gilbert" Subject: Re: [Elecraft] Lighted displays Hi, Ron. Here's a few reasons why I did it: 1. For portable operation, it's not always easy to get a single lamp to shine down on the operating table and toward the face of the rig at the same time. You'd need the lamp behind you, and the operating platform (table, whatever) is usually in front of you. Since I like using a laptop computor for logging, I don't really need an operating lamp at all if the display is otherwise visible. 2. For portable operation, I need fewer total lumens of light (and therefore fewer total milliamps of current) to put the light precisely where I need it. I can get by with only one extra LED (in addition to the K1 display) for paper logging. 3. I like to operate Field Day, as can be seen from AB7E (+K7ZB) results in 1B-2op category the last few years (we hit an even 10,000 points this last year running 5 watts, albeit prior to my getting the K1). During a contest, at least when in search/pounce mode, I can often identify a station from the frequency they are on even before they send their callsign. There are certain calls you work -- and then hear over and over again throughout the rest of the contest and you can waste a lot of time listening for their ID. 4. I think a lighted display is pretty, and it only cost me 5 milliamps from the battery, which is roughly 10% of the normal receive current. I'm sure I will even notice the difference in battery life at that draw. The modifications I made are internal and don't even show up when you look inside the rig since the LEDs, resistor, and wires all fit between the front panel and the front circuit board. By the way, it was nice chatting K1-to-K1 with you the other evening. I simply worked on some other stuff in the shack while I monitored 14060 until you showed up per your emails to the reflector. Your signal was perfectly readable on my dipole. Take care, Dave AB7E K1 #412 - ----- Original Message ----- From: Ron Willcocks To: Sent: Friday, March 23, 2001 11:47 PM Subject: [Elecraft] Lighted displays > I have seen several reports on the reflector about lighted displays for the > K1. > I have to wonder why???? > If I was going camping in the sticks and operating off batteries I still > wouldn't need a lighted display...Why not you ask??....I have my K1 setup so > it is about 200hz off the bottom of the band and as it covers only about > 90khz, I am not going to be out of band at the bottom, or in the SSB portion > above. Lets face it...most QRP contacts are made from answering CQ's > anyway. > If I needed light at all it would be for logging. It is hard to keep a log > in the dark, so why desicrate a perfectly good rig for the sake of having > the display lit?? Your rig battery will last longer without a lit display. > Shine the torch on it between using the log.......... Much more (Mojo ??) > commonsense to me! > Cheers......Ron ZL1AJP +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ To: elecraft at mailman.qth.net Date: Tue, 14 May 2002 00:39:32 -0500 From: n4so at juno.com Subject: [Elecraft] K1 LCD Illumination mod Sandy W5TVW lcd.txt LCD illumination mod Jim, N2CAU explained his mod for LCD illumination back in Jan. 2001. This is an edited text file. A mini-lamp is installed in the K1 on the left side of the LCD display and is held in place by double sided tape. The mini-lamp is a Radio Shack 272-1141, 12 volts at 25 mA. The mini-lamp comes with 2 inch leads, and an extra 6 inch extension to the leads was added and one side of the lamp was connected to ground and the other side to pin 16 on the front pc board. I think he refers to P1 (to FP-J1) on Appendix B K1 RF board, bottom of the page, below the Buffer 2N3906. Pin 16 is marked 12V connected to C34/C36. Jim says it works and you use up an additional 25 mA and the connection is made with no on/off switch. Jim, N2CAU james at panzita.com 23 Jan. 2001 Ken Brown-N4SO Mobile, AL EM50tk Elecraft K-1 4 ele. monoband yagi N4SO at juno.com ++++++++++++++++++ Date: Tue, 14 May 2002 06:50:03 -0500 To: "John J. McDonough" , elecraft at mailman.qth.net From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] K1 LCD Illumination mod If you placed several of them in series, you could add up to about 8-10 LEDs with NO increase in current, and you'd not have to dissipate nearly as much heat in the dropping resistor. NOT that I'm advocating using a bunch of them, but if they're in series, you CAN reduce the size of the current limiting resistor. Tom Hammond N0SS At 05:43 AM 5/14/02, you wrote: >----- Original Message ----- >From: >Subject: [Elecraft] K1 LCD Illumination mod > > > Jim says it works and you use up an additional 25 mA and the > > connection is made with no on/off switch. > >Wow, for 25 mils you could get away with a couple of LEDs. > >72/73 de WB8RCR http://www.qsl.net/wb8rcr >didileydadidah QRP-L #1446 Code Warriors #35 +++++++++++++++++++ From: "Don Brown" To: "Elecraft" Subject: Re: [Elecraft] K1 LCD Illumination mod Date: Tue, 14 May 2002 08:50:06 -0500 Hi It wouldn't matter if its on the 12 or 5 volt supply. If the led is runni= ng at 20 ma then the power is dissipated in either the limit resistor or = the regulator so the net result is still 20 ma more on the battery. It is= better to keep the extra current off of the regulator so it will run coo= ler. There are some very high efficiency LED out there and can be run at 5 - 1= 0 ma with plenty of brightness for night use. look at the HLMP-3950A gree= n, HLMP - 3750A red, HLMP - 3850A yellow by HP or QT Optoelectronics. I u= se these led's in several products I make and they are very bright even a= t low currents. Two of these in series one on each side of the display sh= ould work well at 5 ma or if you have room try 4 in series. There are som= e white led's available now that are very bright if you didn't like red, = green or yellow Don Brown KD5ND ++++++++++++++++++++++ Date: Tue, 14 May 2002 13:28:11 -0700 From: lhlousek Subject: [Elecraft] K1 illumination To: elecraft at mailman.qth.net I put 2 small high brightness green LEDs in series and mounted one on each side of the LCD angled so as to illuminate the LCD. Plenty of light at 10 mA but illuminating the LCD from the edges doesn't work very well. The LCD looks washed out and most of the light winds up illuminting the inside of the K1. I took them out and use an external LED light to illuminate the display, and the buttons and even my note pad. It only takes about 10mA to provide adequate light if your eyes are dark adapted. Of course they won't be if you have the ATTN or RIT LEDs on. HI! Lou W7DZN +++++++++++++++++++++ Date: Tue, 14 May 2002 13:25:05 -0700 (PDT) From: Jessie Oberreuter To: lhlousek Cc: elecraft at mailman.qth.net Subject: Re: [Elecraft] K1 illumination I had a similar experience. I tried both red and white leds inside the case and didn't get worth-while results. I may try again in the future. I also turned the RIT/XIT led around during construction; now it matches my Icom, makes more intuitive sense to me, and lets me RIT around w/out being blinded :). On Tue, 14 May 2002, lhlousek wrote: > I put 2 small high brightness green LEDs in series and mounted one on each side of the LCD angled so as to illuminate > the LCD. ++++++++++++++++++++ Reply-To: "John J. McDonough" From: "John J. McDonough" To: Subject: Re: [Elecraft] K1 illumination Date: Tue, 14 May 2002 22:00:32 -0400 Well, youse guys made me do it. I put a 1900mcd yellow LED (Radio Shack) in each corner of the display. Behind the front panel, tho, I taped a piece of white paper with a hole for the display so a bunch of the light could get reflected off the front. I also made some baffles to keep the light from being quite so obvious around the buttons. Actually, works pretty well. Not like an actual backlight, but plenty of illumination to see the display, and with the paper in there, it appears to come from all around the display. 72/73 de WB8RCR http://www.qsl.net/wb8rcr ++++++++++++++++++++ From: "Sandy, W5TVW" To: "John J. McDonough" , Subject: Re: [Elecraft] K1 illumination Date: Wed, 15 May 2002 15:28:44 -0500 Well! I took the "plunge" today! Local "Rat Shack" store had the yellow and the white LEDS. I bought both. Like the white ones the best. They are expensive....but makes the K1 a real 'night-time' radio now! My total receive drain is 58 ma. with 13.5 volt supply. Illumination looks the same on the 8 "AA" Ni-MH cell supply! I used stock number 276-320. I picked up the ground on the "loop" terminal and the +12 volts on pin 16 of the board 20 pin socket. Used #20 insulated hookup wire as it was "stiff" enough to support the LEDs. A 1500 ohm 1/4 watt carbon resistor interconnects the LED's over the LCD pins. Strips of stragetically placed #33 Scotch electrical tape used as insulators and also "masks" to minimize light going towards the RIT/XIT LED and switch cutouts. This would be a VERY worthwhile "mod" to incorporate in a future Panel PCB revision! Also, some "flat" high intensity white or yellow or green LEDs would be better than the round 5mm sized ones. Thanks to all for the suggestions! IO originally thought of using the teeny-tiny grain of wheat 12 v. lamps, but this adds no additional current drain worth talking about! Additionally, they will probably NEVER need replacement! 73, Sandy W5TVW K1 S/N 1178 ++++++++++++++++++ Reply-To: "John J. McDonough" From: "John J. McDonough" To: Date: Sun, 26 May 2002 10:27:00 -0400 Subject: [Elecraft] K1 LCD Illumination A number of folks have asked how I arranged the LEDs that I showed in http://www.qsl.net/wb8rcr/K1Light.html I got enough emails that I decided to write it up in a web page, complete with step by step pictures: http://www.qsl.net/wb8rcr/K1LEDhowto.html Enjoy 72/73 de WB8RCR http://www.qsl.net/wb8rcr didileydadidah QRP-L #1446 Code Warriors #35 ++++++++++++++++++++ To: elecraft at mailman.qth.net From: n4so at juno.com Date: Wed, 01 Jan 2003 13:41:30 EST Subject: [Elecraft] K1 LCD Illumination K1ILLUM.TXT I prefer the LED approach for low power consumption and long life. No switch is a good idea. Here are saved files from 23 Jan. 2001/and 2002 for K1 LCD illumination, another approach James Panzitta N2CAU used a mini-lamp Radio Shack 272-1141 It is 12 volts at 25 mA. Tie point for 12 volts is pin 16 and ground on the front pc board RF panel 20 pin IC socket. There is no switch. N2CAU james at panzitta.com From: "Sandy, W5TVW" Date: Wed, 15 May 2002 15:28:44 -0500 Subject: Re: [Elecraft] K1 illumination Well! I took the "plunge" today! Local "Rat Shack" store had the yellow and the white LEDS. I bought both. Like the white ones the best. They are expensive....but makes the K1 a real 'night-time' radio now! My total receive drain is 58 ma. with 13.5 volt supply. Illumination looks the same on the 8 "AA" Ni-MH cell supply! I used stock number 276-320. I picked up the ground on the "loop" terminal and the +12 volts on pin 16 of the RF board 20 pin socket. Used #20 insulated hookup wire as it was "stiff" enough to support the LEDs. A 1500 ohm 1/4 watt carbon resistor interconnects the LED's over the LCD pins. Strips of stragetically placed #33 Scotch electrical tape used as insulators and also "masks" to minimize light going towards the RIT/XIT LED and switch cutouts. This would be a VERY worthwhile "mod" to incorporate in a future Panel PCB revision! Also, some "flat" high intensity white or yellow or green LEDs would be better than the round 5mm sized ones. Thanks to all for the suggestions! I originally thought of using the teeny-tiny grain of wheat 12 v. lamps, but this adds no additional current drain worth talking about! Additionally, they will probably NEVER need replacement! 73, Sandy W5TVW K1 S/N 1178 N4SO Ken Brown Mobile, AL/EM50tk NorCal-20/5 watts/4 ele. beam N4SO at juno.com +++++++++++++++++ From: "Wallace, Andy" To: "'Elecraft'" Date: Wed, 19 Mar 2003 10:11:59 -0500 Subject: [Elecraft] RE: K1 display backlight - well, a possibility if LCD swapped Things must be really slow; I'm replying to my own message! I just found that Lumex makes a backlight that may fit: http://www.lumex.com/pls/lumex/subproduct_galary?iproduct_id=1001050 SSB-DL3117xxx -- xxx being color. 30.5 x 17mm edge lit backlight panel, available in several colors including green. So if someone wanted to order the transreflective Varitronix display, and then the Lumex backlight, it may actually work! You'd have to bend the leads (since there are no board holes for a backlight) and run power/dropping resistor. Digikey carries Lumex and Varitronix; maybe they can special-order. See below for LCD info. Andy > -----Original Message----- > > K1 display is V L Electronics VI-321-DP-RC-S-12 > > Mech Dwg > http://www.varitronix.com/catalog/lcd_spec/VI321.PDF > about 18x30 mm > > Pinout > http://www.varitronix.com/catalog/lcd_spec/VI321.html > > Main display page: > http://www.varitronix.com/catalog/slcd1.html > > Looks like -RC is reflective. Transreflective would be > VI-321-DP-FC-S-12, so if we could get one of those, and find > the proper backlight to wedge underneath, we'd be set! +++++++++++++++++ From: "Wallace, Andy" To: "'Elecraft'" Subject: RE: [Elecraft] RE: K1 display backlight - well, a possibility if LCD swapped Date: Wed, 19 Mar 2003 17:33:03 -0500 > ----- Original Message ----- > From: "Wallace, Andy" > > | I just found that Lumex makes a backlight that may fit: > | > | http://www.lumex.com/pls/lumex/subproduct_galary?iproduct_id=1001050 Well, I heard from Lumex and this is a special order part, with tooling costs, etc. Perhaps someone else makes a 15x30mm backlight. Here's one thing I just found: http://www.lumitex.com/specifications.html (PDF brochure above) Fiber optic backlighting -- an LED feeds into a fiber optic weave which is slipped under the LCD. Seems ideal! No idea about price/availability, etc. I have to laugh sometimes, since we're down to modding dial lights on the K1 - the rig is great, so all we have left is cosmetic improvements. ;-) Andy ++++++++++++++++++