RE: [Elecraft] K2 backlighting brightness
A few bits about LEDs, including a response to Ron, ZL1TW's question about dimming over time. LEDs do dim over time. Since they usually do not suffer catastrophic failure that stops all output altogether (like an incandescent bulb does when the filament fails) their end of life is typically measured as the point at which the light output has dropped to 1/2 the original design value. That operating life is generally in the vicinity of 100,000 hours. LEDs can harm your eyesight! Peering directly into an LED can cause eye damage. They are NOT lasers, but they can be very bright - much brighter than an incandescent bulb of that size. The issue is that the light is being emitted from a much smaller point source than other types of lamps, including incandescent bulbs. You have nothing to fear from incidental light from an LED, but some manufacturers warn against looking directly into an LED at close range. LEDs are current driven, not voltage driven. That is, the current through the device determines the brightness and, unfortunately, the temperature of the semiconductor inside. Higher than normal currents produce device heating that will reduce the light output and decrease the operating life. Like most epoxy-encased semiconductors, LEDs can EXPLODE when subjected to serious over-currents. The bang is small, but the lamp sprays epoxy shrapnel around. It could raise havoc with an eyeball that is close to it when it happens. Actually, that's true of many types of transistors when subjected to big over-currents, but LEDs seen to be the ones people are peering at when they go off! There's nothing to worry about if they are being operated at their proper current levels. The only danger is when the current-limiting resistor is not correct for the voltage source. LEDs can be damaged by ESD. Actually ANY semiconductor junction can be: it's a matter of how big of an ESD charge reaches is. Most diodes are pretty hard to hurt, so you won't find warnings to wear a wrist strap when handling them in the Elecraft manuals. Still a jolt can do damage to an LED junction. It's no where near as robust as, say, a power supply rectifier diode. Ron AC7AC -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of AA5CK Sent: Wednesday, July 12, 2006 10:07 PM To: ron_w Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K2 backlighting brightness Hi Ron I went through this a few weeks ago. After trying several different value resistors in parallel with R 10 I ended up with a 39 ohm one. This dropped the the total resistance to about 18 ohms and increased the current from the original 24 mA to 34 mA. Still not as bright as #5523 but close. Further increase in current didn't seem to increase the brightness much so I went with the 39 ohm resister but YMMV. I don't know about LEDs dimming but an increase in current may shorten their life. Hopefully 5 mA per pair won't have a significant effect. Maybe we'll get a more definitive answer from the list. This is really not a big problem and I am certain I would have never noticed the difference in brightness had the two rigs not been setting side by side and even then it took several days before I noticed it. Good LuckTed...aa5ck ron_w wrote: Both K2's go remarkably the same, but the older K2 has a noticeably dimmer display than the new one which raises the questions :- (1) Do the back light LED's dim with time? ..the older K2 *has* had a lot of use. (2) Would changing R10 to (say) 22ohms have any detrimental effect on the life of the back light LCD's? . Cheers...Ron ZL1TW ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Elecraft@mailman.qth.net 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] Re: Elecraft Digest, Vol 27, Issue 14
On Thu, 2006-07-13 at 04:02 -0400, [EMAIL PROTECTED] wrote: Re: Blackwidow (Nick Waterman) Using a piece of plate glass and some spray adhesive, you can take sheets of 400, then 600 all the way to eight hundred grit wet/dry sand paper and fix it to the plate glass. That surface can be used to bring up a shine so bright on the key that you can see your reflection in the surface. I might consider beveling the edges on the base and the arms for a more refined look. Jim WX9J #4892 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] XV50 on 70MHz
I have been very pleased with My K2 which I purchased at Dayton back in 2005. So pleased, that I have persuaded a few others to take the plunge and build K2s, here in the UK. I have been looking at the feasibility of building an Elecraft XV50 for the 70MHz band to use with my K2. Interest in this band is mushrooming in Europe with new countries gaining 70MHz allocations almost on a monthly basis. ( http://www.70mhz.org ) The modifications required would seem to be fairly straightforward but I have no illusions to be an RF design engineer! The Mitsubishi RA30H0608M power module would be a drop in replacement for the M57735 (using the XV144s biasing circuit). There would need to be a few L and C value changes in the TX LPF and the mixer BPF too. The LO would have to be changed to 42MHz (from 22MHz). I am a bit confused on the choice of driver SGA7489 in the XV50, ERA-5 in the XV144 and back to the SGA7489 in the XV222. Presumably the SGA7489 would be OK at 70MHz? Has anyone on the list already done all of the above? I have no wish to re-invent the wheel. I would be pleased to hear of the component values required. There does not appear to be anything specific in the archive. Whilst I am aware that Elecrafts core market is in the US and Canada, I think they are missing an opportunity to create a successful new product for a very minimum of RD effort. I think an Elecraft XV70 would do well in Europe as there is a lack of any competition for equipment on this rapidly expanding band. The XV series have very flexible interfacing and I am sure would prove a popular way for stations to get on the band with their existing HF transceiver. It may even encourage a few more European VHF hams to go on and build a K2 as well! 73 Allan GM4ZUK ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: Phone jack problem
Hi Ron, Because we use a K2 for CW contesting (Multi -one and Multi-Two) and need dual headphone output, I set up a dual headphone pair of sockets under the bench - it keeps the op's headphone cord from laying across the computer keyboard and enables a trainee op to watch and listen to the contest. I don't want to damage that front panel headphone socket.G 73, Ken ZL1AIH (ZM1A, ZL6A in the IARU Contest) ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] XV50 on 70MHz
In message [EMAIL PROTECTED], Allan Duncan [EMAIL PROTECTED] writes snip Whilst I am aware that Elecraft’s core market is in the US and Canada, I think they are missing an opportunity to create a successful new product for a very minimum of RD effort. I think an Elecraft “XV70” would do well in Europe as there is a lack of any competition for equipment on this rapidly expanding band. The XV series have very flexible interfacing and I am sure would prove a popular way for stations to get on the band with their existing HF transceiver. It may even encourage a few more European VHF hams to go on and build a K2 as well! Totally agree with Allan's post above. I am currently 'modding' my old 6m transverter back to 4m, but would buy an XV70 without hesitation. Trev G3ZYY -- Trevor Day UKSMG #217 www.uksmg.org ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K2 backlighting brightness
At 06:28 PM 7/12/2006, ron_w wrote... would such a change give me more back light without compromising components in the Front panel board?(ie U3). I doubt there is a problem but it is always wise to ask .. If you're equipped to desolder the display, you could replace the backlight LEDs with brighter ones. I used two Everlight EL-94-22UBGC arrays, which are available in the US from Mouser for a couple of buck each ( http://www.mouser.com/catalog/626/41.pdf ). They fit perfectly, I think the originals from Elecraft are the Everlight EL-94-22VGC. The relative brightness of these two different LED arrays is 133 vs. 35 mcd @ 20 ma, a very significant difference in brightness. They do change the display from green to a blue-green color. I was then able to use a _larger_ R10 dropping resistor to get acceptable brightness (can't remember what I ended up with), so now I get the same current draw regardless of the day/night setting (with the night setting, the main display uses more power, but the meter LEDs use less). ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Re: For Sale: K1 w/ ATU + 6 Bands + Accessories
I'm reducing the price on this to $365.00 delivered via Priority Mail to the lower 48. Again, please reply direct if interested. - JT On 7/12/06, JT Croteau [EMAIL PROTECTED] wrote: Selling my well loved K1 with four two band filter boards, ATU, and a few accessories. K1 #292 - 2 Band Model recently aligned for the following filter boards: 40/80 20/15 17/30 It will also come with a fourth filter board for 20/40. KAT1 is included along with the tilt stand with only the short legs (long legs were lost by the previous owner). The K1 is in excellent working order and great physical shape. Elecraft mods include all updates from Rev. D to Rev F. specs and the backlight mod. Original manual is included along with all documentation for the installed modifications. I will also include the following: . Bulldog Mini-Paddles . 2x9.6V 2000 mAH NiMH Packs w/ wallwart charger all wired to powerpole connectors Some photos: K1 with mini-paddles: http://img100.imageshack.us/img100/3682/k12nk.jpg One of the two included battery packs: http://img362.imageshack.us/img362/1212/battery7qb.jpg Price: $400.00 shipped via USPS Priorit Mail to the lower 48. Payment via PayPal is preferred but I will also take a money order via the mail. Email direct to [EMAIL PROTECTED] if interested. I am selling to finance an ATS-3 and invest the remainder in another hobby. -- JT Croteau - W6FO - Canton, GA | K1 #292 ARS #2,147 | NoGA-QRP | SEDXC | ARRL ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Polishing Brass (was Blackwidow)
And if you really want it to glow, don't stop with the 600 or 800 grit paper, visit your automotive paint supplies place and you will find grits much finer than that, 1200 and 1600 are common and often 2400 grit sheets can be found. These are wet/dry type papers, use with water as a lubricant and the grit will not fill up. You can obtain a real mirror finish, it just takes time and effort. 73, Don W3FPR -Original Message- Re: Blackwidow (Nick Waterman) Using a piece of plate glass and some spray adhesive, you can take sheets of 400, then 600 all the way to eight hundred grit wet/dry sand paper and fix it to the plate glass. That surface can be used to bring up a shine so bright on the key that you can see your reflection in the surface. I might consider beveling the edges on the base and the arms for a more refined look. Jim WX9J #4892 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] OT: Parts
Hello All, I have a large amount of various new small parts (primarily 1/4 watt resistors including 1% types, board mounted pots, capacitors fixed and variable, fuses, etc). Some of these I have hundreds of the same values. If anyone is looking for parts, please let me know. I am in need of board mounted RFCs (various), 100K 1/4w, and some other items. Would like to trade stuff. Please contact me off list. Cheers, Julius n2wn ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Black Widow Paddle
I wonder if using a power sander, which has a soft rubber backing pad, will cause rounding over of the edges of the parts for the Black Widow paddle... I read the instructions for polishing the brass in the Black Widow paddle using fine sandpaper...The problem is that the sandpaper quickly loads up and stops cutting...I would go to an automotive paint supply and buy wet-or-dry emery paper...Wet or dry is usually a gray color on the back side with black abrasive on the business side... Tape the paper to the table as suggested, then apply a small amount of water to it and start sanding...The water will hold the metal particles in suspension and allow the paper to continue cutting, and the cutting will be FAST...As the cutting continues, the water will thicken into a brass colored slurry which can be rinsed or wiped off, after which sanding can continue using the same sheet of sandpaper...This method is excellent for polishing the edges of plexiglass... Jerry, wa2dkg ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K2 S/N 5556 Transmitter Alignment
Hello all, This is my first post to the group so I hope it works correctly! Happy to report that K2 S/N 5556 is alive in Australia! However I'm slightly concerned about the results I'm getting during transmitter alignment. After running through the TX alignment procedure twice the best results I can get for max power out are as follows: 80m - 8.1w 40m - 9.6w 30m - 10.8w 20m - 14.5w 17m - 13.6w 15m - 9.1w 12m - 10.5w 10m - 10.6w These power figures come from the internal K2 power meter but a CB radio pwr/swr meter connected between K2 and 50 ohm commercial dummy load agrees with these figures with surprising accuracy. The question being are these output figures 'normal'? Output on 80m, 15m and perhaps even 40m seems a bit low to me. Simply because I'm expecting to see 10w or more on each band. In addition I got a 'Hi Cur' warning are soon as I raised the power level to maximum. My K2 consistently draws 2.69A on all bands according to the digital current meter in the power supply but the K2 current meter registers values from 2.52A to 2.54A. I'm inclined to believe the K2 but as yet have not checked the current draw with a meter. I have for the moment increased the 'Hi Cur' warning threshold to 3.0A. Again, same question, is this current draw 'normal' or abnormally high? I have double checked the 80m bandpass filter components, toroid type/number of turns and the capacitor values and all appears to be correct. So I'm not sure if I have a problem or not. A sincere thanks guys for all your combined help getting me to this point. No I haven't posted to the list before but when confused (and that happened regularly !-) my questions were always answered by the list archives! Cheers from 'down-under' Steve VK2SJA K2 S/N 5556 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Black Widow Paddle
I build and repair 1911 semi-auto pistols. All the internal parts are hand polished and they are much harder than brass. You can do this while watching TV if you want as it's rather mind numbing. Depending on the surface roughness start with the 600 and progress up by 200 gr each sheet. 1000 should give you a pretty good surface finish. As Don says if you want more shine go on up to 1600. I've even gone to 2000 but really didn't see the benefit. A power sander will roll the edges plus can cause other problems, really fast! When I'm in the shop I use a marble tile to work on, 3/4 thick so it won't move. In the house watching TV I use a board in my lap with a piece of glass on it. Put the sand paper on the surface, wet it and go to polishing. I prefer to use oil on metals, the puddle lasts longer. If you change your oil in your car then you have what it takes. I've been using synthetic motor oil for years so this is what I use for the polishing media as I always have it on hand. Pour a puddle of oil and go to it. With the 600 and 800 you are trying to knock off the high points or rough cuts so polishing in a circle is ok. You last few cuts of paper make sure you polish the long direction as it will leave a grain direction in the final product. Taking out a swirl will drive you crazy. This process will give you a bright as you want surface then remember with brass you have to coat it or it will tarnish. A brass coat works, I've used clear epoxy spray or even car wax works. As you can see it's an easy job just takes time. Also using the oil I've never had to tape or glue the sand paper down. Once it's wet on a flat surface it doesn't move. Paul K7PM ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K2 S/N 5556 Transmitter Alignment - Doh!
G'day again, I feel such a fool! I almost have to ask everyone to disregard my previous post. After turning off all the equipment ready to shuffle off to bed (it's very late/early here) I'm looking at the lab style bench power supply that I'm using an realise that it's max supply current is only 2.5A. I was hitting the current max of the supply and it was going into 'current limit' dropping the supply voltage to about 10-11 volts and I had not realised. Switching to a slighly larger lab supply capable of 3.0A output changes things slightly! I'm now getting the following power output from my K2:- 80m - 17.2w 40m - 16.5w 30m - 15.7w 20m - 15.6w 17m - 15.6w 15m - 14.5w 12m - 14.0w 10m - 11.5w Again these figures from the internal K2 power meter but the CB radio pwr/swr meter agrees. Very happy chap with these figures :) So now the only question that remains is the current draw. The K2 now shows current draw values between 2.58A and 2.92A. Is this current draw 'normal' for these power output figures? Cheers, and sorry to trouble the group with my false alarm! Steve VK2SJA K2 S/N 5556 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K2 VCO Test and no VCO ref voltage
Hi, I am building my second K2. First K2 no challenges at all but with this one I am falling down at the first major hurdle. Freq 10482.69 and should be between 8 to 10 MHz. Trouble shooting no help. VCO alignment - DMM reads 0.02V at R30 (should be 6V). Any pointers much appreciated. 73, Mark, G3XYS (on or off line) ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K2 S/N 5556 Transmitter Alignment - Doh!
Steve, Honestly, if we had a contest for the most unbelieveable, boneheaded, mindless mistakes ever made in electronics, you wouldn't even come in the running. I would beat you and everyone else on this list so badly, they would have to give points to even it up. Just shake it off and go to the next step. Regards, Vin Cortina KR2F K1-4 s/n:1977 KX1 s/n:1476 (even still under construction) -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Stephen Arnold Sent: Thursday, July 13, 2006 11:30 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K2 S/N 5556 Transmitter Alignment - Doh! G'day again, I feel such a fool! I almost have to ask everyone to disregard my previous post. After turning off all the equipment ready to ... ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K2 S/N 5556 Transmitter Alignment - Doh!
Steve, FB on your power supply confusion there. The answer to your question depends on the voltage out of your power supply (under load). If it is only 12 volts, then my answer is yes, the current draw is OK. But if your power supply is developing 13.8 volts or a bit more, then your current draw is a bit on the high side of normal. It is not so high that it would be something to worry about. If you limit the power to 12 watts, you will normally see 2.5 amps or less on all bands except for 10 meters. Partial explaination: The K2 does internal power level control and will try to ramp up the power to the level requested by the POWER knob. To develop 12 watts with a 12 volt supply requires more current than if the voltage is higher - it is a simple matter of Volts times Amps equals Power - the more volts, the less current required since the K2 tries to keep the power constant. 73, Don W3FPR -Original Message- I almost have to ask everyone to disregard my previous post. After turning off all the equipment ready to shuffle off to bed (it's very late/early here) I'm looking at the lab style bench power supply that I'm using an realise that it's max supply current is only 2.5A. I was hitting the current max of the supply and it was going into 'current limit' dropping the supply voltage to about 10-11 volts and I had not realised. Switching to a slighly larger lab supply capable of 3.0A output changes things slightly! I'm now getting the following power output from my K2:- 80m - 17.2w 40m - 16.5w 30m - 15.7w 20m - 15.6w 17m - 15.6w 15m - 14.5w 12m - 14.0w 10m - 11.5w Again these figures from the internal K2 power meter but the CB radio pwr/swr meter agrees. Very happy chap with these figures :) So now the only question that remains is the current draw. The K2 now shows current draw values between 2.58A and 2.92A. Is this current draw 'normal' for these power output figures? Cheers, and sorry to trouble the group with my false alarm! Steve VK2SJA K2 S/N 5556 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K1 problem
On Wed, 12 Jul 2006 18:46:56 -0500 Dr. Dan Swartling [EMAIL PROTECTED] wrote: I am half-way through building my K1 # and have hit a stumbling block. How are trimmer caps C13 and C20 installed? On the revision E board it is not obvious (to me) which way to orient the flat side. Cool serial number! I had the same problem. I looked them up in the parts placement drawing at the back of the assembly manual and here I could clearly see how they should be mounted. The flat side should face towards the back of the PCB. A rather bad picture, but this may help too: http://www.oz9aec.dk/pictures/gal/Homebrew/Elecraft_K1/K1-0048.jpg Dan 73 Alex OZ9AEC K1 #2172 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] XV50 on 70MHz
Yep Allan... I'm here .. ready to build a 70 mhz transverter if there is one from Elecraft ( with components included ) !!! hope cu from Jean louis 3A/F5NHJ.. if needed.. K2 #5371 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K2 backlighting brightness.
Hello Ron, and the List. I've got K2 #0681 #2681 sitting next to each other here, both glowing happily - and equally! I wonder, could it be that brighter leds were used in the later K2s?? Cheers, 73 to all. Mike, zl1mh. -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.394 / Virus Database: 268.10.0/388 - Release Date: 13/07/2006 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] FW: [Moon-net] Elecraft K2 IF for EME
Hi everyone, I am forwarding this partial email thread from the Moon-net list to everyone here on the Elecraft list in hopes to generate a good discussion (not a flame war!) on the use of the K2 for weak signal use. I would appreciate hearing all responses to this subject because I was considering using the K2 (or maybe the K3?) for weak signal work someday. What are the major strengths/weaknesses of the K2 in this area, and what can be done to improve this. There are some very knowledgable people on this list and your experience in this area would be most appreciated. Thanks, Tony K4YYZ -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Sergio Sent: Wednesday, July 12, 2006 4:08 AM To: D.W. Harms Cc: Moon Net Subject: Re: [Moon-net] Elecraft K2 IF for EME All, I used to have a K2 and I share the same comments you have mentioned as well as Shawn's one. Aside a number of minor things, I was mostly annoyed by the bad ripple of the IF filters too, which is not a trivial thing. They kept the filters area still at a 'very kit level' , maybe it would have been better to put some extra effort there. Another major draw back for me it was the 10Hz step tuning, which with the very tight DSP set at maybe 50Hz BW it didn't really ensure a proper operation in CW/weak signals. Yes one could eventually set the RIT as the 'fine resolution tune' but then the split function was lost and, in my case, I could not compensate the doppler anymore thus being obliged to use another rig in TX... This is just to report my practical experience, it is not my intention to bias any soul. Aside this, I also have to report that building the radio was definitely a nice experience bringing a lot of satisfaction and excitement during its progression. Sergio IK2MMB D.W. Harms wrote: Hi Don e.e. Besides my home mde transceiver I have the K2 with a built in DEM transvertor (144-28 ECK) in use since Januari 2004. In combination with the transvertor it slightly outperforms my home made transceiver. I can highly recommend the radio! There are only two things that bother me: 1. The throughput gain on 28 MHz seems to be low. I made a seperate output on the rig to bring the 28 MHz signal to my Drake R7/Tr7 combination and I have obviously more signal there. This of course could influance the overall noise floor... The K2 really marvels at the lower HF-bands, but the front-end filters on 28 MHz are not that good. That is probably why the excellent strong-signal behaviour for which the K2 is well-known, is not too obvious on 28 MHz. I sometimes think about replacing the frontend filters, or to change the IF to 14 MHz. 2. The IF-filter seems to produce some ripple, as reported by another ham here on moonnet. Of course this is a killer in weak signal work! I have not noticed it myself, but heard others (PA0CHN) complain about it. It was fun building the radio during the x-mas holidays together with my youngest son. So if you are looking for a heatkit-like project, then go for it! It is a superb radio for portable work. I use it in combination with a 300W mosfet amp for MS-work and have good experiences. It is probably much better than the average portbale multi-multi band rice-boxes... I am not too sure yet if it is the best radio for weak-signal EME work. I have to do some more investigation. It is hard to judge given the fact that I have lots of urban noise, something that EVERY radio would suffer from hi! I also saw a remark about microphones. Well, I have used the K2 wit both an electret and a MD-microphone. Both worked well, though you should not expect HIFI reports... But then again, I am no fone-fan so I dont bother too much... VY 73, Dick PA2DW Is anyone using the Elecraft K2 transceiver on 28 MHz as the IF in an EME system? If so I would appreciate your evaluation of the K2 in terms of receive capability of weak EME cw signals. Please reply direct to [EMAIL PROTECTED] ___ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] FW: [Moon-net] Elecraft K2 IF for EME
I actually posted the start of this thread here a couple of days ago .. They've got valid points for EME, but they don't apply so much to typical VHF/UHF contest work. I've only got one rove in using the Elecraft stuff .. the low band station worked great once I got the right combination of IF cables and Ts. Strong signal performance was great, conditions were so poor that there wasn't much weak signal around :( The high band station ended up using an IC-706, but that was a failure in the 144-28 xverter .. we used the K2 as the bandswitch, because I had integrated everything from 903-10G using a custom-mapped KRC2 I'll have more to say in the fall after I get more experience and tweak out some bugs, but so far I like it de w1rt/john On 7/13/06, Lanier, Robert [EMAIL PROTECTED] wrote: Hi everyone, I am forwarding this partial email thread from the Moon-net list to everyone here on the Elecraft list in hopes to generate a good discussion (not a flame war!) on the use of the K2 for weak signal use. I would appreciate hearing all responses to this subject because I was considering using the K2 (or maybe the K3?) for weak signal work someday. What are the major strengths/weaknesses of the K2 in this area, and what can be done to improve this. There are some very knowledgable people on this list and your experience in this area would be most appreciated. Thanks, Tony K4YYZ -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Sergio Sent: Wednesday, July 12, 2006 4:08 AM To: D.W. Harms Cc: Moon Net Subject: Re: [Moon-net] Elecraft K2 IF for EME All, I used to have a K2 and I share the same comments you have mentioned as well as Shawn's one. Aside a number of minor things, I was mostly annoyed by the bad ripple of the IF filters too, which is not a trivial thing. They kept the filters area still at a 'very kit level' , maybe it would have been better to put some extra effort there. Another major draw back for me it was the 10Hz step tuning, which with the very tight DSP set at maybe 50Hz BW it didn't really ensure a proper operation in CW/weak signals. Yes one could eventually set the RIT as the 'fine resolution tune' but then the split function was lost and, in my case, I could not compensate the doppler anymore thus being obliged to use another rig in TX... This is just to report my practical experience, it is not my intention to bias any soul. Aside this, I also have to report that building the radio was definitely a nice experience bringing a lot of satisfaction and excitement during its progression. Sergio IK2MMB D.W. Harms wrote: Hi Don e.e. Besides my home mde transceiver I have the K2 with a built in DEM transvertor (144-28 ECK) in use since Januari 2004. In combination with the transvertor it slightly outperforms my home made transceiver. I can highly recommend the radio! There are only two things that bother me: 1. The throughput gain on 28 MHz seems to be low. I made a seperate output on the rig to bring the 28 MHz signal to my Drake R7/Tr7 combination and I have obviously more signal there. This of course could influance the overall noise floor... The K2 really marvels at the lower HF-bands, but the front-end filters on 28 MHz are not that good. That is probably why the excellent strong-signal behaviour for which the K2 is well-known, is not too obvious on 28 MHz. I sometimes think about replacing the frontend filters, or to change the IF to 14 MHz. 2. The IF-filter seems to produce some ripple, as reported by another ham here on moonnet. Of course this is a killer in weak signal work! I have not noticed it myself, but heard others (PA0CHN) complain about it. It was fun building the radio during the x-mas holidays together with my youngest son. So if you are looking for a heatkit-like project, then go for it! It is a superb radio for portable work. I use it in combination with a 300W mosfet amp for MS-work and have good experiences. It is probably much better than the average portbale multi-multi band rice-boxes... I am not too sure yet if it is the best radio for weak-signal EME work. I have to do some more investigation. It is hard to judge given the fact that I have lots of urban noise, something that EVERY radio would suffer from hi! I also saw a remark about microphones. Well, I have used the K2 wit both an electret and a MD-microphone. Both worked well, though you should not expect HIFI reports... But then again, I am no fone-fan so I dont bother too much... VY 73, Dick PA2DW Is anyone using the Elecraft K2 transceiver on 28 MHz as the IF in an EME system? If so I would appreciate your evaluation of the K2 in terms of receive capability of weak EME cw signals. Please reply direct to [EMAIL PROTECTED] ___ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html
RE: [Elecraft] FW: [Moon-net] Elecraft K2 IF for EME
Tony, I do not have any real experience with weak signal VHF work, but I do have some comments about the K2 on a technical basis that may help in your decisions. I would be interested to know what the filter width was in use that generated those comments as well as the serial number of the K2 that was being used for that evaluation. Some of those deficiencies have been addressed and corrected along the K2's migration progress. The facts as I know them - the K2 SSB filter has very little ripple in the passband. The filter crystal specs (for all the IF crystals) were improved between Elecraft and the crystal vendor and the improved crystals have been in K2s since SN 2560. Secondly, the variable width (CW) filter on the RF board presents a smooth single-nosed passband if the filter width is set to 1000 Hz or less. Wider passbands do tend to break up into multiple peaks which may be troublesome to some applications, but that is the downside to attemting to use a filter designed for best response in the 400 to 600 Hz width range at a very wide setting - it works OK for SSB voice reception, but it certainly is not an optimum filter shape. Yes, the K2 is limited to 10 Hz steps - that is just part of the design compromises that were deemed acceptable Even RIT does not circumvent this limitation - the firmware controls the steps and RIT works through the firmware. For Satellite work, several folks have previously commented that the biggest downside for the K2 is the fact that the frequency cannot be changed while transmitting. That may not be a factor in many situations but where the transmit frequency must be changed to compensate for doppler, all I can say is that the K2 was not designed to do that task. Maybe the K3 or K? (if it ever gets into the product plan) will address that problem. The 28 MHz bandpass is broader than the others, and could possibly be improved if designed for a more narrow passband, but for HF use, that bandpass filter must be rather wide - as it is now on the K2, the speced 10 meter band is 28.0 to 28.8 MHz rather than going up to 29.7, so some compromises have already been put in place. The one nice thing about the K2 is that it can be changed to better meet the needs of a particular group of folks if desired - the network is nothing more than a double tuned bandpass filter, and the filter components can be altered for a more narrow peak if that is desirable. 73, Don W3FPR -Original Message- I am forwarding this partial email thread from the Moon-net list to everyone here on the Elecraft list in hopes to generate a good discussion (not a flame war!) on the use of the K2 for weak signal use. I would appreciate hearing all responses to this subject because I was considering using the K2 (or maybe the K3?) for weak signal work someday. What are the major strengths/weaknesses of the K2 in this area, and what can be done to improve this. There are some very knowledgable people on this list and your experience in this area would be most appreciated. Thanks, Tony K4YYZ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] F/S K1 4 band XCVR
I have a very nicely built late serial # (21xx) K1 for sale with 40, 30, 20 and 15 meter band filters, KAT1 ATU and the new lighted display. Also includes a nice homebrew tilt bale. Radio is in excellent condx in all respects w/full output power on all bands. All manuals and 'spare parts' included. Price $450.00 delivered/insured to CONUS (postal money order only please). Pix/more info please contact me off line. [EMAIL PROTECTED] Thanks for reading, Lou - W6UR ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] FW: [Moon-net] Elecraft K2 IF for EME
Hi Don and the others. I'm an EE and here are some things to consider. For EME the K2 will be driving the transmitter via a high level mixer and the receiver will be a converter built to tune 432 MHz. If I were doing it I would mix down to 14.000 to 14.350 MHz. This makes the good things about the K2 fully functional :-) The S/N is a total function of the first RF stage of the converter at 432 MHz IF the stage gain is 15 DB or more. If you don't have enough gain you can put an IF stage in the converter. The 10 HZ tuning step is kind of odd to me. My At-Sprint 3 has a DDS frequency generator that is of a step type. It is around 10 Hz too. My Yaesu radios tune smoothly and the FT-817 has been a great radio for EME work. It is very common now. The 817 has a little phase lock loop noise that the gain of the converter masks with signal+noise from 432 MHz. And you can buy the ultra stable crystal oscillator kit for the 817 that makes it very stable. The standard crystal oscillator is not good enough :-) 73 Karl K5DI Don Wilhelm wrote: Tony, I do not have any real experience with weak signal VHF work, but I do have some comments about the K2 on a technical basis that may help in your decisions. I would be interested to know what the filter width was in use that generated those comments as well as the serial number of the K2 that was being used for that evaluation. Some of those deficiencies have been addressed and corrected along the K2's migration progress. The facts as I know them - the K2 SSB filter has very little ripple in the passband. The filter crystal specs (for all the IF crystals) were improved between Elecraft and the crystal vendor and the improved crystals have been in K2s since SN 2560. Secondly, the variable width (CW) filter on the RF board presents a smooth single-nosed passband if the filter width is set to 1000 Hz or less. Wider passbands do tend to break up into multiple peaks which may be troublesome to some applications, but that is the downside to attemting to use a filter designed for best response in the 400 to 600 Hz width range at a very wide setting - it works OK for SSB voice reception, but it certainly is not an optimum filter shape. Yes, the K2 is limited to 10 Hz steps - that is just part of the design compromises that were deemed acceptable Even RIT does not circumvent this limitation - the firmware controls the steps and RIT works through the firmware. For Satellite work, several folks have previously commented that the biggest downside for the K2 is the fact that the frequency cannot be changed while transmitting. That may not be a factor in many situations but where the transmit frequency must be changed to compensate for doppler, all I can say is that the K2 was not designed to do that task. Maybe the K3 or K? (if it ever gets into the product plan) will address that problem. The 28 MHz bandpass is broader than the others, and could possibly be improved if designed for a more narrow passband, but for HF use, that bandpass filter must be rather wide - as it is now on the K2, the speced 10 meter band is 28.0 to 28.8 MHz rather than going up to 29.7, so some compromises have already been put in place. The one nice thing about the K2 is that it can be changed to better meet the needs of a particular group of folks if desired - the network is nothing more than a double tuned bandpass filter, and the filter components can be altered for a more narrow peak if that is desirable. 73, Don W3FPR -Original Message- I am forwarding this partial email thread from the Moon-net list to everyone here on the Elecraft list in hopes to generate a good discussion (not a flame war!) on the use of the K2 for weak signal use. I would appreciate hearing all responses to this subject because I was considering using the K2 (or maybe the K3?) for weak signal work someday. What are the major strengths/weaknesses of the K2 in this area, and what can be done to improve this. There are some very knowledgable people on this list and your experience in this area would be most appreciated. Thanks, Tony K4YYZ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] Resistance Checks During Front Panel Assembly
Hi all. I just got my K2 in the mail this morning (hooray!) and I've been busily assembling. I did the control board and all checked out there. Now I've soldered most all of the front panel and I got to the resistance checks and ran into a problem. Now when doing the resistance checks so far, when the manual says a range, things have been in that range. When the manual says 50k or 1M, things have been fine. My meter reads something (usually about 4-6M). So I went through the resistance tests three times but I'm running into problems. The first 40 test points (the pins on the LCD driver IC, U1) worked fine. Everything was as expected. Then I got to the 20 tests on J1. The first 7 pins of J1 (measured at the solder point) are all OL which is my meters way of telling me that the probes aren't connected. In other words, infinite resistance. Most of the rest of J1 works. Pin 8 measures zero, pin 10 measures 4.4M (should be 50k), pin 12 and 14 both work (6.6M), and everything 15 and above checks out too. Pins 1-7, 9, and 11 all register as unconnected. I've even tried measuring from other pads that are connected by traces (for example, some of those connect to where the shaft encoder will go) but they still register unconnected. Everything looks soldered well, I see no bridges, etc. I've build tons of kits, I'm quite confident in my skills. I just need to know what to check. -- Michael Cook ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Resistance Checks During Front Panel Assembly
Michael, OL may also mean out of range. Take the auto ranging off your DMM. OL may just mean resistance is higher than current range allows, or something. Vin Cortina KR2F K1-4 s/n:1977 KX1 s/n:1476 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Michael Cook Sent: Thursday, July 13, 2006 9:22 PM To: elecraft@mailman.qth.net Subject: [Elecraft] Resistance Checks During Front Panel Assembly Hi all. I just got my K2 in the mail this morning (hooray!) and I've been busily assembling. I did the control board and all checked out there. Now I've soldered most all of the front panel and I got to the resistance checks and ran into a problem. Now when doing the resistance checks so far, when the manual says a range, things have been in that range. When the manual says 50k or 1M, things have been fine. My meter reads something (usually about 4-6M). So I went through the resistance tests three times but I'm running into problems. The first 40 test points (the pins on the LCD driver IC, U1) worked fine. Everything was as expected. Then I got to the 20 tests on J1. The first 7 pins of J1 (measured at the solder point) are all OL which is my meters way of telling me that the probes aren't connected. In other words, infinite resistance. Most of the rest of J1 works. Pin 8 measures zero, pin 10 measures 4.4M (should be 50k), pin 12 and 14 both work (6.6M), and everything 15 and above checks out too. Pins 1-7, 9, and 11 all register as unconnected. I've even tried measuring from other pads that are connected by traces (for example, some of those connect to where the shaft encoder will go) but they still register unconnected. Everything looks soldered well, I see no bridges, etc. I've build tons of kits, I'm quite confident in my skills. I just need to know what to check. -- Michael Cook ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Elecraft@mailman.qth.net 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: [Elecraft] Resistance Checks During Front Panel Assembly
OL may also mean out of range. Take the auto ranging off your DMM. OL may just mean resistance is higher than current range allows, or something. Vin Cortina KR2F I just tried that, as well as my other DMM, and the same thing is still happening. For what it's worth, I think the guts of my second meter (sold by Radio Shack) are actually made by the same company as my first meter (Metex Instruments). I tried both auto ranging (as I keep the meter on) and the highest range (dual digit mega-ohm, so it could show 37.5 M for example). I have installed the parts on the board that you install for the KSB2, for what it's worth. I don't think that would change anything, but there you go. There is a tiny chance I have an old analog meter somewhere, I'll hunt for it tomorrow. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Resistance Checks During Front Panel Assembly
On Jul 13, 2006, at 8:36 PM, W6NEK wrote: Hi Michael, I get the same type Open Circuit resistance readings as you and my K2's worked just fine. All it means is the series resistance between J1 Pins 1 - 7 is greater then 10 megs to ground which my DMM reads as Open Circuit. If I were you, I would proceed with the build. I think all is fine with your build so far. 73, Frank - W6NEK PS - I have built 11 K2's so far and they all acted the same as far as high resistance readings are concerned. Thanks, that is kind of what I was thinking. I saw the note that 50k can read as open, but it threw me for a loop because up to that point everything that said 50k had read something, but all of a sudden some of the pins weren't doing that. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Resistance Checks During Front Panel Assembly
WATCH OUT, WATCH OUT! Do NOT dig out that old analog meter unless you KNOW it's designed for modern solid state gear. Making a single measurement with it can fry more I.C.s, diodes and transistors than you may care to count! Older meters put way too much voltage on the circuit and allowed way to much current to pass for modern devices. Open circuit is 50 K, or whatever so your find with any such readings. Ron AC7AC -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Cook Sent: Thursday, July 13, 2006 7:24 PM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] Resistance Checks During Front Panel Assembly OL may also mean out of range. Take the auto ranging off your DMM. OL may just mean resistance is higher than current range allows, or something. Vin Cortina KR2F I just tried that, as well as my other DMM, and the same thing is still happening. For what it's worth, I think the guts of my second meter (sold by Radio Shack) are actually made by the same company as my first meter (Metex Instruments). I tried both auto ranging (as I keep the meter on) and the highest range (dual digit mega-ohm, so it could show 37.5 M for example). I have installed the parts on the board that you install for the KSB2, for what it's worth. I don't think that would change anything, but there you go. There is a tiny chance I have an old analog meter somewhere, I'll hunt for it tomorrow. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Elecraft@mailman.qth.net 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] coil info
Can some one tell me the person who is winding the coils for the k2 have a friend who wants some coils wound Sincerely Harold n5tog ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] coil info
mailto:[EMAIL PROTECTED] - Mychael winds great toroids and his prices are reasonable. You can download his price list and order form at the Elecraft website 73, Don W3FPR -Original Message- Can some one tell me the person who is winding the coils for the k2 have a friend who wants some coils wound Sincerely Harold n5tog ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] Resistance Checks During Front Panel Assembly
Michael, A resistance reading stated as 50k can indeed be an open circuit. Infinitity is greater than 50k. One reason they are should not listed in the manual as open circuit is that many meters will respond to just the resistance of your body should you make contact with the probes. If you follow the schematic, you will indeed find that at this point of assembly, those points are really open circuits. The resistance check is mainly to find any solder bridges or other assembly errors - since your meter reads as though they are open circuits, all is well. There is a statement that the high resistance readings may actually indicate infinite resistance, exactly as you have found to be true. No need to use another meter to check anything. 73, Don W3FPR -Original Message- Hi all. I just got my K2 in the mail this morning (hooray!) and I've been busily assembling. I did the control board and all checked out there. Now I've soldered most all of the front panel and I got to the resistance checks and ran into a problem. Now when doing the resistance checks so far, when the manual says a range, things have been in that range. When the manual says 50k or 1M, things have been fine. My meter reads something (usually about 4-6M). So I went through the resistance tests three times but I'm running into problems. The first 40 test points (the pins on the LCD driver IC, U1) worked fine. Everything was as expected. Then I got to the 20 tests on J1. The first 7 pins of J1 (measured at the solder point) are all OL which is my meters way of telling me that the probes aren't connected. In other words, infinite resistance. Most of the rest of J1 works. Pin 8 measures zero, pin 10 measures 4.4M (should be 50k), pin 12 and 14 both work (6.6M), and everything 15 and above checks out too. Pins 1-7, 9, and 11 all register as unconnected. I've even tried measuring from other pads that are connected by traces (for example, some of those connect to where the shaft encoder will go) but they still register unconnected. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] XV50 on 70MHz
I have been so pleased with my XV50 that I have just started using on 6m, that I would jump at the chance to buy an XV70 to be QRV on 70MHz. Please Elecraft, think seriously about producing one. 73 de Chris, G4BUE On 13 Jul 2006 at 9:45, Allan Duncan wrote: I have been very pleased with My K2 which I purchased at Dayton back in 2005. So pleased, that I have persuaded a few others to take the plunge and build K2s, here in the UK. I have been looking at the feasibility of building an Elecraft XV50 for the 70MHz band to use with my K2. Interest in this band is mushrooming in Europe with new countries gaining 70MHz allocations almost on a monthly basis. ( http://www.70mhz.org ) The modifications required would seem to be fairly straightforward but I have no illusions to be an RF design engineer! The Mitsubishi RA30H0608M power module would be a drop in replacement for the M57735 (using the XV144s biasing circuit). There would need to be a few L and C value changes in the TX LPF and the mixer BPF too. The LO would have to be changed to 42MHz (from 22MHz). I am a bit confused on the choice of driver SGA7489 in the XV50, ERA-5 in the XV144 and back to the SGA7489 in the XV222. Presumably the SGA7489 would be OK at 70MHz? Has anyone on the list already done all of the above? I have no wish to re-invent the wheel. I would be pleased to hear of the component values required. There does not appear to be anything specific in the archive. Whilst I am aware that Elecrafts core market is in the US and Canada, I think they are missing an opportunity to create a successful new product for a very minimum of RD effort. I think an Elecraft XV70 would do well in Europe as there is a lack of any competition for equipment on this rapidly expanding band. The XV series have very flexible interfacing and I am sure would prove a popular way for stations to get on the band with their existing HF transceiver. It may even encourage a few more European VHF hams to go on and build a K2 as well! 73 Allan GM4ZUK ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Elecraft@mailman.qth.net 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
