NoseyNick's (G7RZQ's) Elecraft K2

"I don't know if anybody else [...] does this, but every time I turn my K2 on, and use it on a DX-ped hour after hour, I sit and look at this itty bitty radio, and am just amazed at how something so small, can be so good! anybody else do this?"

Yes. This is normal behavior.

-- K7ZUM and KZ1X, Elecraft Reflector Mailing List

I have neglected my Amateur Radio hobby for too long. In the intervening time, licensing has changed and I'm now allowed to use the HF bands. In an effort to get back into the hobby, and particularly onto HF, I have decided to buy and build an Elecraft K2 kit.

Yes, it's a kit. I get to build a really respectable HF Amateur Radio transceiver, with top-notch performance, for about a third of the cost of anything vaguely comparable, though obviously I have to invest a lot of my precious TIME too. At the end of it, I end up with a radio that I UNDERSTAND, not a sealed box of unexplained tricks made in the far east using technology I'm unlikely to be able to tweak or repair.

I decided to put together this page to document the entire process from start to finish, in case it helps anyone else.


Choosing it

Well, first I was drooling over an Icom 756 pro with all the pwetty gwaphs and colour displays and stuff, but I knew I couldn't afford it until I win the lottery. The 746 pro was another option, but still cost far too much, and anyway, both of these are mass-produced manufactured boxes of tricks, there's none of that experimental spirit of Amateur Radio

At some point I became interested in the "Tayloe Detector" I'd read about in an article somewhere. It might have been "A Software-Defined Radio for the Masses, Part 1" found on ARRL's SDR page. This is a fantastically neat little detector (the main core of a receiver) which I could understand. I'm mostly a digital chap, I understand ones and zeros, and all the analogue stuff with non-linear mixers and bandpass filters and beat frequencies and things scare me, yet the Tayloe Detector pretty much de-multiplexes your radio frequency into 4 buckets representing 4 phases of the signal you're tuning. It's analogue, but it's simple analogue that digital geeks can understand. This could be a receiver I could build myself, and then I could write software to do most of the rest of the pretty displays and decoding data modes and everything...

... except it's not even a whole receiver, let alone a transmitter too...

Then I found that the "Tayloe Detector" wasn't actually some brand new invention, it's otherwise known as a "commutating mixer" or a "differential quadrature switched mixer", maybe a "multi phase sampler". Also, of course, it's "only" a mixer, not a whole receiver, and definitely not a whole transmitter as well. I was looking forward to Dan Tayloe's transceiver coming out as a kit, but it was taking too long, it was CW-only, 20m or 30m only, QRP (low power) only, and whilst exploring around, I discovered a graph in a presentation by Dan Tayloe comparing performance versus power drain of many transceivers including Dan's prototype, the Elecraft K2, the ten-tec orion, and various "YaeComWood" bits of kit. The Ten-Tec one looked to be the best performer (apart from Dan's rig of course), better than the Icoms I was previously drooling over, but eats power and costs a fortune.

The K2... Hey, here's an interesting one, performs damned well (almost as well as Dan's CW-only rig), doesn't eat juice too much, SSB option, all major amateur bands, comes as a KIT, and (thus?) costs considerably less than anything anywhere near its class. It seems you could easily pay 3 times as much for a rig that would perform far worse!

I've built electronic gizmos before, including stuff I designed myself and stuff in ready-made kits. This wasn't going to be trivial, but sounded like fun!

So I can't wait for Dan's rig, which seems to be CW-only (Morse) anyway. The "second best" rig (the orion) costs a fortune and eats power. The "third best" rig is the K2, uses more power than Dan's, but nowhere near as much as the big shiny boxes, it costs a fraction of the big shiny boxes, and outperforms most of them. What's the catch? I need time to build it myself, and hey, I might even UNDERSTAND IT after I build it bit by bit! Fantastic!

A bit more web-searching

I stumbled across a page mentioning both EARS and the K2, and I was reminded that I have a local club - Echelford Amateur Radio Society. It was probably this page about them using a K2 in a recent(ish) amateur radio contest (full results of the contest).

Well, I exchanged a few emails with their webmaster, and then decided to turn up to EARS one week. They had a GSM talk, which is related to my work, and I had a good chat with some of the guys there too. A week and a bit later, I went to their Field Day - basically one of the competitions like the one above. They set up a big tent, 2 masts, a vast antenna and a rig, and then for 24 hours, you try to talk to as many other hams around the world in as many countries as possible on as many bands as possible. The scoring is complicated but involves counting the number of contacts and multiplying up by all sorts of things. Sometimes one contact can earn not only a couple of points, but hundreds because it's also multiplied your total by 2! It was a lot of fun, it was also a great way for me to learn a bit more about the K2 and its options, and operating HF (or contesting at least!). I became a lot clearer about what bits I need, what bits I don't need, etc etc.

I joined the Elecraft reflector - a mailing-list for owners, builders, and potential owners of Elecraft Kit - the K2, K1, KX1, etc etc. Way too many posts, but quite a few of them are useful!

I tried the Elecraft IRC channel and was told: "Ian, g0vgs, K2/100 #4044, go for it, you will not be disappointed" :-)

Investigating options / Shopping List

Description Needed when Suppliers / Part #s / costs
A better soldering iron? I've got a cheap and nasty one, badly tinned and seemingly impossible to tin right. Might be worth investing in a semi-serious temperature-controlled one for a project of this magnitude. "Soldering equipment is critical. You will need a good, temperature-controlled soldering station". Elecraft recommends the WTCPT station with PTF-7 1/32" tip for K2 construction. Grounded tip also v. good. Before building Maplin N78AR £12.99
(until 12/24/2005)
Maplin BP53H £49.99
Rapid 85-0550 £45.24
Rapid 85-1046 £45.82
Better solder? "Elecraft recommends 60/40". Solder is cheap, and nice new solder is bound to work better than the crummy aged stuff I'm using, which quite possibly belongs to a plumber rather than an Electronics constructor. EU RoHS directives are phasing out lead though, so I'll probably have to go for a lead-free alternative. Nigel G8IFF said "You go buy lead free solder, preferably silver loaded, and start using it. No changes needed to your normal soldering methods". Multicore? .015 dia probably easier than .032 Before building
(if at all)
Maplin Ag/Sn/Cu
250g 215°C £7.99

Rapid 85-6612 100g 217°C £3.76
Rapid 85-0595 500g 60/40 188°C £7.05
Antistatic strap? I've usually got away with touching something earthed, but again for a project of this magnitude, it might be worth investing in - they're not expensive, and may save me a load of re-ordered parts. Before building Maplin FE29G £2.99
Maplin ZT91Y £2.99
N Antistatic mat maybe? (Decided to use tinfoil) Before building? Maplin ZT95D £9.99
(until 12/24/2005)
Rapid 87-2952 £18.51
A DMM that'll do resistance and capacitance, maybe even inductance? I have an old analogue meter which manages resistance, manual ranging and everything, but it won't help me check capacitor values and it's a bit inaccurate even at resistance. Before building Maplin N81CB £49.99
Little crocodile / alligator clips for meter probes Before building
(If at all)
Maplin min crocs? 42-52p
Kempton 30p?
N Magnifying glass? Some of the bits are very small and have even smaller writing. PCB holder? Poss,
before building
Maplin YK53H £4.99?
The K2 (duh!). UPS shipping. >>>K2#5209 has arrived!<<< Main phase Elecraft K2 $599.00
qrpp K2 EUR 750
KSB2: The SSB board - I don't know Morse yet and need this for any of the voice or data modes. ( notes ) Main order Elecraft KSB2 $99.00
qrpp EUR 119
KPA100: The 100 Watt power amp. Dennis at EARS regretted not getting it first time 'round. QRP is apparently a lot of fun once you're an expert, but not a fun way to start on HF. "If you're interested in QRP, we suggest that you save it for the next step, rather than try to make it your first step"... Anyway, it also includes the same functionality as... Main order Elecraft KPA100 $369.00
qrpp EUR455
N ... KIO2: The IO interface for computer control. It's what I do! Main order (Inc in above)
KAT100-1, or possibly pic-a-tune or something: An ATU. I don't have space in my garden for a properly tuned antenna, and such an antenna would also be tuned for "the band of my choice" and I don't yet know enough about the bands to choose only one, let alone one that would fit in my garden. No, seriously, random length of wire, as much as I can get away with, and an ATU to make it work properly. Got to be the way to go.
Something to consider: the KPA100 and kat100 can be built into a separate EC2 enclosure as shown by kk7p and ki6wx. This allows the k2 to be built with all the QRP options including internal battery, and to be run as a QRO (full power) base station by plugging into the KPA100/kat100 when at home.
Main order Elecraft KAT100-1 $239.00
qrpp EUR 298
... or ...
Elecraft KAT100-2 $219.00
qrpp EUR 274
+Elecraft EC2 $59.00
N ETS15 or ETS2 tilt stand? 1.5" for KAT100 or or 3" for EC2? Sounds like the K2 comes with one, but might need one for separate EC2/KAT100? (Maybe later) Main order? Elecraft ETS15 $11.50
Elecraft ETS2 $11.50
FDIMP Finger Dimple - just makes tuning up and down the bands a bit easier. Main order Elecraft FDIMP $4.50
A 50 ohm dummy load (possibly DL1?) rated for at least 10W When testing K2 Elecraft DL1 $25.00
N "External wattmeter" OR dummy load above may allow voltmeter to be used as a wattmeter When testing K2 (DL1+DMM)
A Noise generator. Useful for testing and aligning the K2's filters When testing K2 Elecraft N-GEN $39.00
A Test Oscillator, useful for setting S-meter level When testing K2 Elecraft XG1 $39.00
Proset-K2 or similar: A headset with mic, so I can listen to radio squawks and squeals without disturbing the family, and also easy enough to use as the primary microphone. It's what everyone seems to use these days. Handheld mics take one too many hands which are better used for writing and typing. Desk mics really don't cut it either. The K2 has a Kenwood-style 8-pin mic connector. Right after K2 Maplin CJ10L £19.99
Rapid 19-6642 £19.92
Maplin A70AC £24.99
Kenwood MC-43S ML+S £24.95
Kenwood MC43s Nevada £19.95
headphone adapters etc Right after K2 Maplin RK55K 85p
My PSU (Power Supply) is inadequate, Should be OK for basic K2 - 13.8V, 5-7A. K2 comes with a suitable plug to make a power cable. I guess I'll need a few more amps if I want to get much out of the KPA100 though - 20A 13.8V! Preferably linear rather than switched-mode but linears are huge and expensive, and switched are small and (comparatively) cheap. Maybe MyDEL MP-4128 or similar? Before building KPA100 ML&S:
Diamond GSV-3000 £149.94
MyDEL MP-250A £89.95
... @Kempton £69.95
MyDEL MP-4128 £69.95
Palstar PS-30M £99.95
Palstar SPS-8250 £99.95
N Inline fuses if my PSU is unfused. 1A 12V for KAT100 Before testing
(If required)
My PSU IS overload-protected
SOME sort of antenna, possibly a horizontal loop, or at least something balanced that can stay up out of kid's reach without requiring a ground system. Before transmitting some possible antennas
and some more
and some more
Feeder for the antenna, possibly twin-feed (300 ohm TV twin-feed?) Before transmitting Maplin XR31J 300Ω 39p/m
- ... and 50 Ohm Co-Ax. I've asked my workmates to dig out some old 10-base-2 RG58 "cheapernet" cable and bring it in for me Before transmitting scrounged
A balun (possibly BL1/BL2), probably 1:1 rather than 4:1 (BL1 build-able as either, BL2 switchable) Before transmitting Elecraft BL1 $25.00
Elecraft BL2 $34.95
Connectors for antenna - BNC for K2/QRP and SO239 for K2/100, maybe BNC-MM male to male BNC, SO239 connectors for K2/100, KAT100, etc Before transmitting Maplin QT54J £2.99 (PL259 patch)
Maplin HL95D £2.13
Maplin BW81C £1.92 +
Maplin BW82D 52p
Kempton £5 for 10
Earth cable Before transmitting Maplin
Radials / etc Before transmitting ?
Earth spike Before transmitting Kempton £7ish
spare IDE type connectors from PCs apparently make a great way to configure the mic jumpers in the K2. When building KSB2 Scrounge?
Maplin FG44X £1.27
Will also need the right mic connector(s) - K2 doesn't come with one! AIM 19-1289 (8 pin female mic plug). Right after KSB2 Maplin FK30H £2.13
Kempton £1.20?
A foot-switch or some other PTT? Right after KSB2 Maplin KW02C £4.99
Maplin DU99H £4.99
? The PSK31 cable bits and PSK31 mods - basically a cable to connect to the computer instead of a "speaker" and "mic". Not only used for PSK31, but for almost any of the other data modes, and if I want to do any of the pretty spectrogram stuff. FatWire (except in db9 shell)? kk9uq or similar interface? dk1htx builds his into k2 case. Also see filter settings for psk31 Sometime soon after Got most bits @ Kempton
Any more needed?
Some combination of:
  • KNB2: Noise blanker
  • KAF2 audio filter
  • KDSP2: The DSP filter (highly recommended, does both of the above and more)
Later projects Elecraft KNB2
Elecraft KAF2
Elecraft KDSP2
K160RX option for the 160m band, mostly 'cos the EARS nets are there :-/ Later projects Elecraft
Transvertors for other bands? Later projects Elecraft
The k2 mostly tests itself, but bitscope is apparently a good PC oscilloscope if/when I decide I want more test equipment Later projects bitscope
When I eventually get around to learning Morse, (g4fon has a good Morse tutor too), (good paddle use), I'll need a Morse key / paddle.
"Llaves Iambic Paddles. Gold plated, excellent, less than $100, shipped!" (says W2AGN).
Kent Paddle Kit KIT - allegedly one of the best keys you can buy.
Black Widow Paddle, from W5JH who designed the AZ ScQRPion paddle - looks nice, recommended on Elecraft List, and A KIT!
A suitable plug is provided with the k2 kit.
Later Black Widow Paddle
Bulldog paddle
amateur radio products
Kent Paddle Kit

☐: Still need
☒: sorted
N: decided against it
-: pending (EG ordered, awaiting delivery)

Shipping and sh**

I asked around on the Elecraft reflector, and contacted a few friends who know a bit about importing stuff from the US to the UK. It sounds like there are some "commodity codes" that can be put on the customs forms on the parcels:

8525 20 99 00for transmitters and transceivers (including kits)
8529 90 40 00for parts / accessories for above
8529 10 00 00for antennas
8527 19 00 00for receivers with internal batteries
8527 21 00 00for externally powered 12V receivers
8527 31 00 00for other receivers

More info on what these codes mean on the uktradeinfo website.

These should legitimately get your parcel zero-rated for customs+excise duty. VAT is still most likely to be payable on anything purchased from outside the EU. There are Elecraft resellers in the EU, but they'll charge their own local VAT, which (depending on how weak the dollar is, and how high their local VAT is) may easily end up costing more than ordering from Elecraft themselves. It's also worth noting that parcelfarce will also charge an admin fee for collecting the VAT, and have also apparently frequently cocked up and wrongly charged duty, which then needs to be reclaimed following a long and laborious process that can take 3 months. UPS and similar carriers usually get it right, but obviously also cost more in the first place. :-(

If your kit is being bought for a VAT-registered company, it might be possible to pay 0% VAT too, but it seems unlikely that amateur radio kit can legitimately be claimed to be for professional use.


2005-11-13Maplin bits ordered
2005-11-14Most Maplin bits shipped
2005-11-14Elecraft bits ordered
2005-11-15Elecraft bits shipped
2005-11-15Most Maplin bits failed delivery
2005-11-17Most Maplin bits delivered
2005-11-21Elecraft bits delivered
2005-11-25Maplin headphones shipped
2005-11-25Mostly inventoried K2 itself - missing keycap, front panel scratched
2005-11-29Maplin headphones delivery
2005-12-03Last 2 bags of K2, Minimods inventoried
2005-12-06KSB2 inventoried - missing wire
2005-12-09KAT100 partly inventoried
2005-12-09Bought UT60E DMM from Maplin Slough
2005-12-10KAT100 inventory complete
2005-12-11KPA100 inventory mostly done
2005-12-12KPA100 inventory complete
2005-12-15Built XG1 with Pb solder. First time I've used my new soldering iron. Takes a little practice, but very very good once it gets going.
2005-12-15Built DL1. Tried AgSnCu solder. It's really quite bad stuff! Needed quite a lot more heat, quite a lot more time with the iron in contact with the components, lucky these are mostly just high-wattage resistors! I suspect I'll be using Pb for K2 itself
2005-12-15Built N-gen, unleaded solder again. Starting to get used to it, but still prefer the Pb stuff.
2005-12-15Built BL2, part leaded, part unleaded. Yup, I'll do the K2 with lead, stuff RoHS!
2005-12-16Started K2 control board
2005-12-18Completed K2 control board, most of front panel
2005-12-19Completed front panel, and RF stage 1, got to that fantastic moment where you power it up and it says "ELECrAFt" in the display!
2005-12-24Some of RF Stage 2 - mostly resistors and capacitors
2005-12-26Almost all of the rest of RF Stage 2, including the terrible toroids!
2005-12-27Finished RF stage 2, did some alignment stuff, heard the Lake District on 40m using only an un-tuned spool of solder as my antenna!
2005-12-29Finished RF stage 3, and TX alignment into DL1
2005-12-30Last few bits of hardware assembly. K2 #5209 is complete!
2005-12-31Posting to the Elecraft reflector, resting, and then hanging some copper in the sky. Random length of wire diagonally across the garden for the moment. Also checked calibration using RWM on 9996kHz - an atomic clock frequency reference in Moscow- after advice from David G4DMP and Sverre LA3ZA. I seem to need to tune 180Hz up. Will fix later. Programmed the IARU beacon frequencies into RCL 1-5 and RWM into RCL 0.
2006-01-01Listening to special event station GB1MGB for Guide Dogs whilst reading the KSB2 manual
2006-01-02I seem to have a low power problem. Low power out, low current drain on the PSU, so something's not providing enough power to the later PA stages. I tried to go through TX diagnostics, by my only "signal generator" is the Elecraft XG1, capable of 50uV out, not 0.14V required by Appendix E. :-(
2006-01-03Dug out an old valve-driven sig-gen and played with it. Better than XG1, voltage-wise, but still not great.
2006-01-04Could kick myself. Borrowed a much shorter 2m bit of much nicer-looking ex-10base2, and put DL1 on the other end of THAT instead of the ropey old 25m bit which I'd previously been using (seemed like a good idea at the time - it was all I had). K2 is fine, I've just wasted lots of testing time that could have been building time.
2006-01-07Built most of KSB2. Arranged to borrow an ATU from Stuart@EARS so I can test TX BEFORE KPA100 + KAT100
2006-01-08Finished KSB2, but found a problem with my BFO, meaning I couldn't CAL FIL properly.
2006-01-09Fixed BFO, not sure how, probably a dry/cold joint caused by the KSB2 rework, but touched most of the BFO-related solder joints with the iron, and re-tested OK. Re-installed KSB2, made some patch cables and things to use Stu's ATU. Theoretically ready to transmit!
2006-01-10Slightly worried - can't hear RWM on 9996. Have I knackered my K2? Do I have to go through all that troubleshooting stuff again?
2006-01-12Can hear RWM again - phew! Presumably I have a lot to learn about 10MHz propagation :-/
2006-01-14RE-calibrated VFO - now within about 30Hz
2006-01-14Made my first ever HF QSO, with Justin G4TSH from EARS (yeah, so just the other side of Staines), just before the RSGB AFS contest. Heard his CQ, recognised the call, couldn't resist. Should probably have asked him to be a bit more critical of my audio etc, but had "first QSO" nerves and rushed it a bit, then left him to enjoy AFS while I went to my daughter's birthday party. Sounds like he'd managed over 17 contacts in the first 7 minutes though - he was storming along!
2006-01-14 13:54 3696kHz
2006-01-16Started a bit of KPA100
2006-01-18Little more KPA100
2006-01-21Fair bit more KPA100
2006-01-22Bit more KPA100, including the initial tests where it plugs into the K2, clicks a bit, and adds some menu options.
2006-01-28KPA100 toroid winding
2006-01-29Little more KPA100
2006-02-10last few KPA100 toroids wound
2006-02-12Heard that Dennis, G3KKQ, from EARS, is a silent key. He had been struggling for a while after a collapsed lung. Not sure if he realised he was one of the reasons I chose the K2. He will be missed.
2006-02-12KPA100 toroids soldered, most back panel construction
2006-02-13KPA100 rest of back panel
2006-02-15KPA100 T1
2006-02-16KPA100 T2
2006-02-19Finished off KPA100. Some voltage tests not quite right.
2006-02-25Tweaked KPA100. Voltage tests are OK with supply <13V.
2006-02-26Finished tweaking KPA100. Tuned up @ 100W. Tested the RS232 serial too.
2006-03-03Made a start on KAT100. Most of the caps.
2006-03-04Bit more KAT100, most of the other smaller components
2006-03-05Almost finished KAT100, including all the relays and toroids
2006-03-05KAT100 resistance checks, joined RF+front
2006-03-07KAT100 hardware bits, control cable
2006-03-08KAT100 tests OK - I now have my own complete home-built Amateur Radio Station!
2006-03-09Returned Stu's ATU and cables. Cheers Stu!
2006-03-12Elecraft QSO party. I'm convinced they're all Americans, or CW, or both. I heard no EU Elecraft SSB :-(
2006-03-12Played with baudline Linux spectrogram software. Can read Morse dits and dahs vertically off the screen. Quite a laugh. I'll use this for precision re-calibration at a later date.
2006-03-17Designed most of my QSL card
2006-03-18Finished my QSL card
2006-03-23Discovered I have a "known issue" whereby the K2 goes deaf when I turn AGC OFF. Will investigate AGC components a bit more, but it looks like I need to replace "5.068MHz AGC crystal" X1
2006-03-25... on the plus side, discovered that my NGEN works fine if given a decent voltage power supply, just not on a nearly-flat 9V NiCad.
2006-03-26YAY! Fixed the AGC: If you are seeing AGC problems (hold PRE/ATT and AGC, see if your K2 goes deaf), check your junk box for a 10pF cap and change control board C8. Wayne says 680 pF at C7 may be another option. I DO NOT recommend this mod UNLESS you're seeing "AGC OFF" issues though.
2006-03-28Played with Voice Over IP - VoIP. I can now listen to my K2 from anywhere in the house over my wireless ethernet. Now I need to sort some remote control software, so I can operate it.
2006-04-12Had a play in the RSGB SSB 80M Club Championships. Did really badly, proved the K2 works, but not great. Probably ought to get around to that re-calibration, and work on getting some more copper higher in the sky - my random unbalanced wire is hardly ideal.
2006-05-23Started to write a simple perl K2 serial terminal, which decodes what you're sending and recieving to the K2.
2006-06-03more simple perl serial terminal
2006-06-11Toothpick mod: Plug / break pin 4 of "AUX IO" connector to make sure nobody plugs in an RS-232 cable
2006-06-11Checked the position of my RFC10 in KPA100 - looks fine
2006-06-25Ordered a Black Widow paddle. I'll have to build it, then I'll have to learn morse :-)
2006-06-26Jerry thanks me for my order, lets me know he's missing some springs but will ship as soon as he can find some more.
2006-07-08Black Widow arrived. No silly duty or VAT or anything to pay.
Tried polishing the base with brasso, without first sanding, at the advice of my father-in-law. Didn't work at all well, could still see manu
2006-07-09Made a couple of contacts with GB5HQ - RSGB stations in the IARU contest.
2006-07-10Tried sanding the Black Widow base. Spent hours with a bit of sandpaper on a flat surface, as per documentation, then tried the buzzy electric sander and got a splendid finish within a minute or two. It's now covered in lots of tiny little swirls, very pretty, matt finish, but I'll probably go for finer polishing until it's mirror-like.
2006-07-12Missing some parts from Black Widow. Let Jerry know. He's going to pop them in the post tomorrow.
2006-07-16Spent some of the last few days sanding and sanding this thing. Spent today assembling most of it. Still need my hex spacers.
2006-07-19Got the missing Black Widow parts
2006-07-20Assembled the Black Widow.
TO-DOCheck Latest KPA100 Errata and see if I need to apply any of it. Mostly P31 of the manual.
TO-DOMake sure the mic connector is properly grounded to the chassis. this is tricky without taking apart the whole front panel.
TO-DOConnecting up some rig control software...
TO-DO... logging software...
TO-DO... VoIP software (sipset? twinkle? kphone? kcall? asterisk? vocalbin?)...
TO-DO... PSK31 software...
TO-DO... other data mode software...
TO-DO... something similar to BeaconSee to monitor beacon frequencies? (See also Ten-Ten beacons)
TO-DOEnjoying them all a bit more!
TO-DOPrecision re-calibration of VFO ("Use the N6KR method for the greatest accuracy"), S-Meter, filters. Try to get all top/bottom-of-band voltages within the 1.5 to 7.0 volt range. See Don's post "Optimum AGC threshold setting" and "Proper Adjustment of K2 AGC". L34 is adjusted for best S/N, not peak signal - try 7000 KHz 'birdie'?
TO-DOLearn Morse
TO-DONext Elecraft/Maplin/ML+S order:
  • 160m module, probably K2 PA H/W kit just in case
  • mag field mods
  • possibly SSBCAPKT to make SSB filter wider, but I'm already 2.4kHz, may not get much benefit from 2.6kHz.
  • ETS15.
  • DSP module?
  • U1, MAR-1 MMIC replacement part for NGEN?
  • Couple of AGC X1 replacements
  • Any PSK31 mod components from the AppNotes page?
  • 10K resistor for KSB2 VOX and gain? Also C34 was 2.2uF now 0.47uF, C31 was 2.2uF now 1uF, C20 was 0.33uF now 0.047uF
  • Kenwood MC-43S hand mic? (MLS?) Maybe MC-80? MC-60A desk mic?
  • Maplin N36CJ storage case? 400mm x 300mm x 180mm

Other notes

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