[Elecraft] K2 #6614
The K2# 6614 has just formally come to life today. Passed Allignment and test part III with flying colors !! Slowly now time for the accessories and options to follow. 73 to all Marinos, sv9dru/ki4gin _ Windows Live Hotmail now works up to 70% faster. http://windowslive.com/Explore/Hotmail?ocid=TXT_TAGLM_WL_hotmail_acq_faster_112008___ 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] RE: K2 VCO Testing problem the stupidity factor...
False alarm guys, I was stupid enough to have D13 installed backwards !! After returning it to its proper orientation, everything is back to normal. Fortunately enough I did not engage in any heroic desoldering action attempts (relays, ICs etc) before I see the cause of the VCO problem Just an advice for the avid builders: When you feel tired, take a break...there is a good reason for feeling tired, do not ignore it. It is like feeling OK to drive after having a couple (or more) drinks!! 73 to all, Marinos, sv9dru/ki4gin Date: Sat, 22 Nov 2008 19:40:35 -0500 From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] CC: elecraft@mailman.qth.net Subject: Re: [Elecraft] RE: K2 VCO Testing problem Marinos, Marinos, Based on your voltage readings at Q18, the VCO is not actually oscillating (indicated by a lack of negative voltage at the gate). I don't know why you have any frequency reading at TP1, but I would tend to disregard it for the moment. The first thing to check is the orientation of D13 and D8. If those are OK, I would try replacing Q18. All other components connected to Q18 are suspect, so check all of them for correct values. Q17 could also be at fault - check it quickly by placing a short from the drain to the source and see if you get a negative voltage on the gate of Q18 - if so, Q17 should be replaced. Also, check the soldering at relays K13, K14 and K15 and the value of C72. Check the varactors D21 through D26 to be certain they are the correct type and oriented properly. 73, Don W3FPR 73, Don W3FPR Marinos Markomanolakis, M.D. wrote: Dear Friends, I am in the process of building my serial# 6614 K2 (the 3rd one that I have built since 2000), and run into a problem during the VCO testing: First, the PLL reference Oscillator test checked within specs, but in the next (VCO) test, while checking at TP1 with the frequency counter,with the K2 at 4.000.10Khz, I am measuring a 7.59 to 7.60Mhz with the last digits of the reading rapidly alternating. The DC voltage at the left end of R30 is about 5.3V with some spontaneous fluctuation, and not responding to adjustment of the L30 as per the VCO alignment test in page 64 of the manual. Reheating the leads of T5, checking C72 and general check for soldering issues did not reveal anything. PLL reference oscillator output with the RF probe: Pin 1 of U4 1.08V (ok), but VCO output signal (pin 3 of U3) 1.13V when only 0.3-0.4V are acceptable and VCO buffer output (pin 6 of U6) 0.85V with the acceptable range being 0.6-0.75V DC measurements : Q18 G 0.0V (-1.0) S 4.3V (2-3) D 7.1V (6.3) U3 Pin# 1 1,1V (0.0) 2 3.9V (4.3) 3 3.8V (4.1)U4 Pin# 3 3.5V (0.0) 7 5.0V (0.0) 8 0.06V (0.1)The values in the parentheses are the acceptable per the manual, and the rest of the IC pins are within specs.Based on the above, I suspect that for some reason the U4 IC might be the problem (eventhough I did observe antistatic and overheating precautions), but since its replacement can be technically difficult and would have to be posponed until the part arrives from Elecraft to the SV1 land, I would like to have your opinion as to how I can further troubleshoot this problem before starting changing parts etc. Thanks, 73 Marinos, sv9dru / ki4gin _ Get more done, have more fun, and stay more connected with Windows Mobile®. http://clk.atdmt.com/MRT/go/119642556/direct/01/___ 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] NB and other improvements and the SMT argument
I would have another thought: Why not redesign a larger K2 with all the necessary options / improvements in a conventional through hole format and plenty of space in the box to have them installed. True this may not be the backpak dream kind of rig, but it can be a high performance base unit. Sometimes if it is very hard to go through a task, you can just bypass it (there are many ways to skin a cat).. 73 to all, Marinos, ki4gin ___ 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] K2/100 for sale
A few people interested but no concrete offers yet: My recently built K2 sn 4618 with the following options is for sale. KPA100 KNB2 KSB2 K160RX KAF2 QRP upper cover configuration and all the Elecraft supplied accessories and documentation also included. Of course the radio was built with professional standards and is 100% cosmetically and operationally. Price: $1150 shipped/insured to CONUS. If interested, please email me off the list. Thanks, 73 Marinos, ki4gin ___ 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] K2/100 sn4618 for sale
Hi to all, I guess I have spent too much time without heating up the soldering iron, and I plan to start building again. My recently built K2 sn4618 with the following options is for sale. KPA100 KNB2 KSB2 K160RX KAF2 QRP upper cover configuration and all the Elecraft supplied accessories and documentation also included. Of course the radio was built with professional standards and is 100% cosmetically and operationally. Price: $1150 shipped to CONUS. If interested, please email me off the list. Thanks, 73 Marinos, ki4gin ___ 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] Can Elecraft take over the ham radio business ?
Hi Guys, Let me re-phrase my original proposal / suggestion about a K3 design with all the features mentioned in my original post: Lets assume that Elecraft had the K2 as we know it, and a K3 more expensive kit with all the useless accessories (IF notch, PBT, general HF coverage, preselector, no birdies etc). Also assume that the K3s performance and specs were equally good to the basic K2 and its price not prohibitive. How many of us would choose the K2 as the main rig over the K3 ?? Would the average ham out there resist the urge of owing such a (K3) rig that he/she built himself instead of a ready made box with inferior basic performance ? My estimation would be not too many, but I may be wrong. 73, Marinos, ki4gin ___ 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: Can Elecraft take over the global HF ham radio business ?
Hi Mike, Thanks for your detailed input on the K2. I personally have built 2 of them, the first in 2001 and the 2nd a couple of months ago sn 4618. I agree 100% with you about the Rx being wonderful, but even in the current revised K2s, needs some refinement, mostly getting rid of the many Rx spurs scattered in several bands. On the other hand, as mentioned in my original post, you can hardly justify keeping the K2 as the only rig for HF, and making those bare bones time proven RF design improvements as well as some more subjective ones that appeal to many of us: (general coverage, notch, pbt,adding a preselector, analog meter, AM receive capability, optimization of the NB, cleaning the spurs from the RX etc) can make the package just too good to be ignored by the majority of the hams. As for the radio being in a kit form, that is actually a HUGE selling point, regardless of the time and effort required to build it since all hams that I have met so far would really love to be able to build their radios instead of buying a ready made appliance, provided that the result does not lack in any significant RF design respect vs the commercially available units. And I am not talking about a million gadgets that you rarely ever use in a rig, but basic ant time proven options as the above mentioned. This is almost a universal definition of a Ham: he who likes to tinker One idea of maintaining serviceability, having excellent shielding between boards and adding options to a complex rig like this is a modular design on a basic motherboard, just like the TR-7, FT901 series etc. That way individual modules can be constructed and tested separately, and many of them can be purchased at a later time as the financial or operational capability of the owner evolves. The real problem is that there is a certain amount of inertia that has to be overcome in the minds of the designers (and customers) before consideration can be given to any significant changes and that can be a very slow process. Of course, the other possibility may be that the K2 in its current version is designed to provide very reasonable performance while being simple enough to maintain a good profit margin for Elecraft. Nevertheless, an updated design does not necessarily have to be cheap (which the K2/100 with options is not), and by gaining widespread acceptance worldwide, profits can be improved even with a smaller profit margin per unit. Just some additional thoughts which for sure will create a lot of commotion in the official mailing list I have absolutely no reservations about the remarkable achievements of the Elecraft design team and I thank every and each one of them for giving us the pleasure of building serious equipment, but evolution and improvement is always good to happen even to the best things in life. 73, Marinos, ki4gin. From: Stricker, Michael [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Can Elecraft take over the global HF ham radio business ? Date: Fri, 29 Apr 2005 08:08:40 -0400 Hi Marinos, I'm not able to post to the board from work but I'll give you my input. I think that if you look at the numbers of K2's sold, it compares very favorably to several of the ICOM radios sold. A couple of examples are the ICOM 765 sold only about 5500 units or so and that is considered an excellent contesting radio and is still sought. That radio was manufactured for about 7 years. The ICOM 756 had a run of a bit less than 5000 and although it suffered from a faulty LCD display, it is still considered a decent radio. That was made for 3 or 4 years before being updated to a pro. The ICOM 775 sold fewer than 3000 units and that had a run of about 5 or 6 years. And lastly, the 781 had a run of near 3000 units for 6+ years. The K2 is 6 or 7 years old so it really is doing pretty well in the realm of high end radios. Personally, I think that it is nearing the end of product life cycle. The QST report on the K2/100 DSP article summed it up quite eloquently in stating that there are only so many buttons available to do so many things and it is now becoming a task to operate all the features. In my opinion, Elecraft would do well by offering the same basic design in a desktop variant so that they could make the controls easier to operate and allocate some of the menu driven functions to independent switch controls or potentiometer/variable controls. The reality is that very few designs that would alter the RF performance would need to change to make it more appealing to a larger market. I'm interested in high performance receivers. I have been through all of the aforementioned ICOMs and opted to procure a Drake R4C and perform all the Sherwood Engineering modifications. That is an impressive piece of equipment. I was going to wait to build a post 5000 serial number K2 however, an opportunity presented itself to buy a very late model serial number K2 that was
[Elecraft] Can Elecraft take over the global HF ham radio business ?
Dear fellow Elecrafters, This is going to be an out of the ordinary post, and I am sure will get quite a bit of criticism, but since there has been a recent discussion about looking for ways to satisfy as many potential customers as possible (with the QRO kits etc), I would like to hear some opinions about this: What are the reasons for the popularity of the K2 radio not being equal to the Japanese made rigs worldwide ? Yes, the rig is very popular but its production/sale numbers are just about 5000, a rather small number compared to any of the commercially available units. In my view, which may be wrong of course, the answer is that the K2 is not considered by the majority of the hams worldwide as the radio that can substitute all others in HF in their shack. It is rather seen as a specialized 2nd or 3rd luxury radio. And here comes the question: Would it be possible and financially profitable for Elecraft to introduce a full feature transceiver kit that can maintain the well known RX advantages of the K2 while adding other features that have come to be considered as standard in modern radios ? * General HF coverage * IF manual Notch * Continuously variable PBT / Rx Bandwidth * Maybe 200W RF output * Band (manual) preselector Of course many people will argue about the usefulness of these features, but having a radio with the above would make it an extremely attractive choice as the only radio for many more hams worldwide, and since the vast majority of us like to build equipment, certainly would prefer it over ready made black-boxes. Just some philosophical thoughts, and topics of debate. 73 to all, Marinos, ki4gin ___ 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] Early failure of the phone plug in a K2
Last night, without warning I had a strange problem with my recently built K2 (sn 4618) : When plugging in my headphones to the connector on the front panel, the K2 speaker was still activated, even though I did have normal sound from the phones too. Looking in the manual, it seems that there is a speaker deactivation switch within the phones female plug which has failed ? Am I missing something ? Anyone with a similar problem ? I suppose now I have to replace the plug... 73, Marinos, ki4gin ___ 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] RF Noise canceller ?
Hi Peter, Would this type of noise canceler not work on white noise also ? 73, Marinos, ki4gin From: Peter Zenker [EMAIL PROTECTED] To: 'Marinos Markomanolakis, M.D.' [EMAIL PROTECTED],elecraft@mailman.qth.net Subject: RE: [Elecraft] RF Noise canceller ? Date: Sun, 3 Apr 2005 13:03:51 +0200 Hello Marinos, There have been several schematics using such technics over the last 20 years. Most of them use a seperate short antenna, feeding the signal pase shifted into a combiner which combines the main Antenna Signal with the phases shifted extra antenna signal. This construction can reduce a lot of man made noise. I remember there was a commercial available stand alone unit sold by a small english company. I myself built such a unit to help reducing my noise problem especialy at 160m (I live in the middle of Berlin, Noise level in the evening is S7) But I forgot the unit during the time because I do not have an 160m Antenna any longer. 73 de Peter, DL2FI -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Marinos Markomanolakis, M.D. Sent: Sunday, April 03, 2005 6:45 AM To: elecraft@mailman.qth.net Subject: [Elecraft] RF Noise canceller ? Just a question for the technically inclined group members: How feasible or worth the effort, would be the addition of an option to the K2 which would sample RF noise from a ferquency close to the used band,(tunable?) which is devoid of signals, phase invert and reinject the noise to an IF stage or even the antenna input in order to cancel our the white or pulse noise components, preserving the desired signal ? Why similar circuits are not preferred in HF receiver designs instead of DSP filters ? Similar circuits are commonly used in biomedical devices (called linear averagers if I am not mistaken) and are very effective in isolating electric signals from a particular organ eg Heart in EKG or brain area of interest in EEG, filtering out the irrelevant noise from the muscle cells... Just some food for thought. ___ 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] RF Noise canceller ?
Just a question for the technically inclined group members: How feasible or worth the effort, would be the addition of an option to the K2 which would sample RF noise from a ferquency close to the used band,(tunable?) which is devoid of signals, phase invert and reinject the noise to an IF stage or even the antenna input in order to cancel our the white or pulse noise components, preserving the desired signal ? Why similar circuits are not preferred in HF receiver designs instead of DSP filters ? Similar circuits are commonly used in biomedical devices (called linear averagers if I am not mistaken) and are very effective in isolating electric signals from a particular organ eg Heart in EKG or brain area of interest in EEG, filtering out the irrelevant noise from the muscle cells... Just some food for thought. ___ 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 NB
A comment about the K2NB and the different reasons that we perceive as being responsible for the lack of its improvement: Just how much would an optimized NB design cost as to become prohibitive for the average Elecraft customer ??? We already have a DSP option costing $300 which many people think as very important and continue buying. An optimized NB is guarantied to be both more important and more desirable feature, which I doubt it very much can approach the above cost. (even if it did I, and many other fellow Elecrafters would still go for it) On the other hand, having such an expensive NB available does not necessarily mean that the current design would have to be discontinued. I am sure there are also many of us absolutely satisfied and delighted by the current NB, and some lucky hams do not even get pulse noise ever at their QTH's. These customers could still have the option of getting this K2NB at its low cost and complexity, but for heaven's sake, give the rest of us urban dwellers the chance to optimize our K2s. Marinos, ki4gin ___ 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] Tune position power adjustment
Hi to all, I have been using my K2/100 #4618 for the last month with marvelous results both in RX and TX. I have also been using a manual ATU to tune my inverted V in all bands, where I have the data on a paper and I adjust accordingly in a matter of a few seconds. The only thing that I do from time to time is to fine tune the SWR depending on the exact frequency within each band, and I use the tune option for this. Even if the power is all the way up to 110W, the rig will output 20W for tuning and that is good, but I only need 2-3W for my fine adjustments which will strain the finals less and create less QRM during the couple of seconds that I need. Here comes the question: Is there any hardware or software adjustment possible that will make the K2/100 put out less than 20W when the tune function is activated even with higher requested power settings ? That would be very convenient in order to avoid having to manually decrease the power to the 2-3W level every time I tune and then having to increase it back to 100W for the QSO. 73, Marinos, KI4GIN ___ 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] Birdie at10m: a choice between a turkey and an ostrich !
Hi to all, I know there was a recent discussion in the forum about this birdie singing at the low end of the 10m band, but did not recall seeing any definitive way to kill it. In my case, I want to think of the birdie living in my K2/100 as a substantially bigger one, a turkey (with the K2100 enabled -power 11w) at 28.266 (USB), Signal strength S2 with the preamp enabled changes to an Ostrich (think logarithmically) of a solid S5 !!! at 28.264 when disabling the 100W option. These two birdies of course are not covered by the background noise of the quiet 10m band and I am sure can/will interfere with Rx down there once it becomes active again. Any thoughts or advice on how to kill/attenuate or move those guys or do I have to live with them ? I can settle for a canary but please help me get these monstrous creatures out of there. 73 to all and enjoy the weekend, Marinos, ki4gin ___ 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] sad news, sorry for the misunderstanding
Ok guys, I got confused, I guess a senile moment .I am equaly sorry for Don's mother, and relieved at the same time that I got everything wrong and Don is alive and well. Thanks for the advice, I will be more careful in the future. 73, Marinos, ki4gin From: Jean-François Ménard [EMAIL PROTECTED] To: Marinos Markomanolakis, MD [EMAIL PROTECTED] CC: Elecraft@mailman.qth.net Subject: Re: [Elecraft] sad news Date: Wed, 5 Jan 2005 16:11:14 -0500 NO NO NO Don's mother. Le 05-01-05, à 16:02, Marinos Markomanolakis, MD a écrit : I am very sorry to hear that Don is no longer with us...He has always been very eager to offer his help in this forum (I just had an email discussion with him last week !) and he has always been so kind. Will be missed. Marinos, ki4gin ___ 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 === Jean-François Ménard / VA2VYZ Elecraft K2 #4130 http://homepage.mac.com/jfmenard === ___ 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] NB design thoughts.
Just wanted to share my experience with the NB in one of my boat anchors, the yaesu FT-401B (tube rig) from the 70's. This NB works almost as good as the best ones I have tried, it does not introduce any distortion in even the strongest signals and has only an on-off switch. (no level adjustment from the rig's front panel even though it does have an internal one via a pot seen at the schematic). This is a NB working at the 3.180Mhz IF of the rig, and the only ill effect I have noticed when turning it on is a reduction of the IF gain which has never made any weak signal unreadable, and of course could be potentially compensated by one subsequent amplification stage anyway. It does though work VERY well for any type of pulse noise. Just with 2 prehistoric FETs and 2 transistors, it has to be the most basic NB design in any rig... Just some food for thought about future improvements in the KNB2 which may not necessarily have to be too complicated. For anyone interested, I have scanned a picture of the NB schematic at the following link: http://photothru.com/share_photoalbum.asp?aid=xA2EF4Bapwd=marko45966[EMAIL PROTECTED] If you have any trouble accessing it, I can email individual copie to anyone interested. 73, Marinos, ki4gin ___ 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] Question about KNB2 Noise Blanker
I do have to agree with the comments for the NB in the K2. I do have power line noise in my QTH which seems to be unaffected by the K2NB, especially when it falls below an S9 level, which sometimes can be the limiting factor in completing a QSO. The majority of the time I have to engage the Preamp in order for the K2NB to start detecting the pulses, and at that level of Rx gain, the receiver may become overloaded by nearby strong signals if present. From all other rigs that have come here at different times, only the NB in a TT Corsair 560 used to behave in a similar way. In order of NB function, the best rigs I have tried so far are TS830, 930 and Drake TR7. For a receiver of the K2 caliber, I believe, it is worth every penny and construction effort, even if it means incorporating a pre-made surface mount module for the NB in order to improve on the NB area which seems to be suboptimal. For example an expensive and/or difficult to build but optimized NB module will be FAR more desirable and effective feature in a real world Rx performance improvement rather than a similar DSP module that is already available from Elecraft. These are my $.02 opinion about the NB, which may be the only area that needs some improvement in a radio that has no equal in the market today. And can definitely make a difference for people wanting to have a K2 as their only/main rig in a urban QTHas most of us live. 73, Marinos, ki4gin ___ 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] KNB2 performance
In general less than stellar performance of the KNB2 circuit in some cases depends on the type of pulse noise that someone tries to eliminate and not to dysfunction of the board itself. It is true that the KNB2 tends to be picky on the type of noise that it is most effective against, but for 90% of the time at least in my current QTH, it does not compare favorably to the NB in other rigs. As for an objective test for the ideal NB, someone can easily have it by operating a TS830 (in good alignment status) side by side with his/her K2. We still love our K2s in fact we love them enough that we like them to have the best possible (analog) performance. This rig has been designed and built with the serious Rx performance in mind from the start, and certainly several weak points have been ironed away since its introduction, so there is absolutely no reason why the NB area should be an exception. Marinos, ki4gin ___ 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] SSB TX signal mystery SOLVED !!!
First let me thank Don (w3fpr) and Garry (ab7my) for their excellent support and guidance for the resolution of this problem. As posted earlier, I had a disappearance of my Tx SSB signal after installing the adaptor to the K2 with normal RX and normal CW Tx. Had spent some hours looking at the different boards without finding the culprit and finally started chasing the SSB signal with the oscilloscope to see where it was blocked. That signal was going fine all the way past the crystal filter, exiting the C5 cap after the T1 transformer but then could not be found at the cathode of D14 That's very strange indeed I thought, since the C5 is supposed to be connected to the cathode of D14 ?!?!? And here came the realization that I had done the STUPID mistake of installing the D14 cathode 90deg away from its normal pad, to a similar pad reserved for the R10.Of course, at a later construction step I had realized that one of the R10 pads was occupied, but I thought it was normal and had soldered it there anyway (another stupidity). Anyway, I can go on and on about how this should never had happened, but it only took a 90deg rotation of this diode without even removing it from the board to fix this. Now I have full SSB output and are 1/2 way done with my K2 100W amplifier board before I have everything up and running. Already built the NB, AF filter and successfully passed the first alignment test of the 100W board The above story is a good example of what happens when you stay up too many hours building your K2. But as you know, when you start you can not easily contain yourself from continuing building. It is addictive !!! 73 to all, Marinos, ki4gin ___ 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] SSB problem update
Update 12/26/04: Did some additional testing with the oscilloscope today and it seems that the balanced modulator IC may be the problem. traced the mic input from the pin #5 of the P1 connector, to the input (U3-pin4) and output (U3-7) of the speech compressor with the expected amplification. The same signal was traced to the input of U5 (pin1). Also the IF signal was detected at the U5 pin 6, as expected, but no modulated RF was present at the U5 output (pin4). The signal at U5-pin 4 was similar in amplitude and frequency to the RF input signal but was not modulated by the AF. Following these results, and given that everything at the Rx side and the TUNE Tx seems to work fine, I believe that the NE612 IC has been damaged. Of course I did observe the proper antistatic and overheating precautions, but one never knows what might have happened to it. Interestingly enough, replacing the main microprocessor chip with an older version 1.06F that I had available, made the AUX BUS (U1-28) voltage go to the expected 2.4 V value in Tx but did not fix the SSB no Tx problem. So I tend to think that the AUX-BUS line is not the issue here. I will order a replacement IC from Elecraft and post the results once I have it installed. Thanks to all that have replied to my question. 73, Marinos. ___ 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] SSB Tx Problem
Season's greetings to all, Well I was thinking that my building experience would be uneventful, after successful completion and testing of the basic K2, but after the installation of the SSB adapter a problem showed up: First, after installing the SSB board everything seemed fine and the Rx filters sounded fine, also did the carrier balance alignment as per the manual (using the K2 S-meter reading) which was fine too. BUT when I connected a Yaesu mic (and another one acted the same) after properly configuring the connector at the front panel board), no Tx output. The K2 goes into Tx mode, Rx muted and the power consumption goes from 240mA in Rx to 440-460mA in Tx but there is absolutely no power out when speaking on the mic at any preset power level. Activating the TUNE option does produce normal RF out just as before. Did inspect the SSB, Control and Front panel boards for soldering problems and found none. Finally did the voltage testing and it seems that most of my measured voltages on the SSB board are slightly lower than expected, for example U1pin9 on TX has 1.08V instead of 2.3V required, with other measurements being significantly lower: Rx (required)Tx (required) U1-21 5.6 (5.8) 0.1(0.02) U1-22 0.13(0.2) 0.0(0.0) U1-25 0.0(0.0) 0.65(0.8-1.2) U1-28 5.6(5.6) 5.47(2.4) ! U2-5 0.47(0.6) 0.6(0.6) U2-8 5.98(6.0) 3.06(5.4) !!! U3-4 1.4(1.7) 1.7(1.7) U3-5 0.2(0.4) 0.4(0.4) U3-6 0.0(0.0) 0.6(0.8-1.2) The above are the most abnormal values, from which I have put exclamation marks at the larger discrepancy values, the first one being the AUX-BUS U1-28 pin of the microcontroller. I tend to think that there lies the sourse of the problem, but have not been able to proceed any further with my diagnostics... Saw some similar postings at the reflector which have been traced to bad solder joints or not removal of the required jumpers from the RF board before installation, but unfortunately, that does not seem to be the problem in my case... Anyone has any ideas?I do have a 40Mhz oscilloscope available, but it seems that this problem might be related to microcontroler communication rather than AF signal loss. 73, Marinos, ki4gin. ___ 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 AGC voltage question
Hi to all and season's greetings. I am in the process of building my K2/100, and have almost finished the RF board of the basic kit. Went through the alignment parts I and II with no problem but have a question regarding 1 reading: 1) During the AGC threshold adjustment (control board) the instructions call for adjustment of the potentiometer R1 until the voltage at the lead# 5 of U2 reaches 3.80V. In my case, the voltage can go to a max value of 3.78V with the R1 being fully counterclockwise. Since the difference is only .2V from the required value, I do not really know if this finding has any importance or needs to be addressed. Any advice would be greatly appreciated. Marinos ki4gin ___ 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
