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Ralph W3GL
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« Reply #25 on: December 06, 2009, 10:31:59 PM »

George,

Your CW tutor missed one character in your first learning  session...

Yes, E, I , S, H, T, M, and O are the first 7 LETTERS but between the  H and T comes "5"...  From one to five dots or dits if you will and one to three dashes or daaws...

Memorize the SOUND of each character and do not count the individual parts of the letters... Do it in your head!  CW is great once you  learn all the characters...

Good luck  and just set the KW2000B aside for a while.  Even though it took all your available funds for Hamming right now, its  price was good, very good, as a matter
of fact.


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73,  Ralph  W3GL 

"Just because the microphone in front of you amplifies your voice around the world is no reason to think we have any more wisdom than we had when our voices could reach from one end of the bar to the other"     Ed Morrow
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« Reply #26 on: December 06, 2009, 10:33:52 PM »

Gee my first rig was a homebrew 6V6GT and a 3725 crystal
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VE3GZB
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« Reply #27 on: December 06, 2009, 10:57:16 PM »

I jumped in and removed the filter, then using the big @$$ soldering iron (est. 300W, 4 pound copper tip, bought it from a flea market for $2), I opened up the filter can. Sure enough, the foam was all Orange goo, just like in this picture:



And one of the wires to the piezo resonator was broken off.

I filled an old jar with Methyl Hydrate, dipped the filter in and let the Orange goo soak for about 5 minutes. That loosened most of it away. I used some clean Methyl Hydrate to tidy up things.

I'm going to resolder the very thin wires back now, then see if I can reassemble things tonight and try it out.

73s
geo
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Ed/KB1HYS
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« Reply #28 on: December 06, 2009, 11:06:58 PM »

Good luck Geo!
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73 de Ed/KB1HYS
Happiness is Hot Tubes, Cold 807's, and warm room filling AM Sound.
 "I've spent three quarters of my life trying to figure out how to do a $50 job for $.50, the rest I spent trying to come up with the $0.50" - D. Gingery
N3DRB The Derb
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« Reply #29 on: December 07, 2009, 12:11:44 AM »

estimated filter loss of -369 db on rx and tx.  Cheesy
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WU2D
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CW is just a narrower version of AM


« Reply #30 on: December 07, 2009, 06:54:11 AM »

George - you are getting distracted by all of this junk - FOCUS!

Get your antenna situation taken care of. First we need to hear your signal.

Seriously, get your little AM rig on the air and make a contact.

Mike WU2D
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K5UJ
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« Reply #31 on: December 07, 2009, 07:23:51 AM »

I recall an article in one of the ham magazines a few years ago on how to clean and restore mechanical filters.

I just searched the ARRL magazine archive and could not find anything.  Maybe it was in CQ.  Anyway you might find something on the internet on this; the article I recall seeing addressed getting rid of all the dried deteriorated foam and getting the filter moving again.

George in some ways you and I are in the same boat.  I have forgotten so much radio and electrical fundamentals or never learned them that I have found I must go back and read starting with the very basic things.  Here are a few books that look good for addressing radio:

The Science of Radio by Paul Nahin
The Art of Electronics by Paul Horowitz and Winfield Hill
AMECO Radio Theory Course for commercial radiotelephone license


The ARRL Handbooks for the 1930s into the early 1950s and these two titles are good for radio and electronics with vacuum tubes:

Electronics by Jacom Millman and Samuel Seely (2nd ed. 1951) McGraw-Hill series on Electrical and Electronic Engineering

This book starts with the motion of charged particles in electric and magnetic fields.

In the same series:

Radio Engineering by Frederick Emmons Terman (3rd ed. 1947)

I get impatient also and want to be on the air with a big maul homebrew or restored boatanchor too but many of the hams in AM have been doing this for decades and we can't catch up overnight  Wink

What you are doing is worth doing.  It is important to get beyond the rut a lot of hams have fallen into over the past 20 or 30 years.  There has been a gradual shift to a majority of hams being consumers of electronics for entertainment purposes only.  Buy some black boxes and set them up with an antenna, turn them on and entertain yourself.  Then whine about the color of the front panel or something.  Technically it isn't that much different from buying a DVD player, hooking it up to a TV set and watching a movie.   Ham radio is supposed to be about doing things, learning and building; not just being a passive receptor of products used to entertain oneself with.   Taken that way you have accomplished quite a bit already in my opinion with your breadboard experimentation even if it has not produced much in the way of on-air contacts.  

How to get old radio books:  Besides on-line used book vendors, University libraries may be trying to get rid of the old books in book sales, or better yet, try contacting E.E. and Physics departments at any college or university near you as often retiring faculty will be cleaning out their offices and wanting to get rid of these old titles.  For most researchers they are considered out of date and not of much use.    The newer Nahin book you'll probably have to buy because it is still in print I believe.  http://www.abebooks.com is a great used vendor and is an aggregator of many small book shops so one search covers many inventories.  I have purchased through them with great results.   I just found the Terman book at Bank Of Books in Ventura Calif. for $6.75  

Good luck & 73

Rob
K5UJ

p.s. Just read Mike's post--a decent antenna for AM is pretty important.   Dipole up 50 feet or more works wonders.
  
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N3DRB The Derb
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« Reply #32 on: December 07, 2009, 07:27:26 AM »

yep, what mike said. You are dodging the real deal, and the real deal is that yer wife wont let you put up a effective antenna because of " looks".

you got that vm 2, thats the key to making a mess of plate modulated goodness. use that 805 you have and fire up the soldering iron. You know how to build and fix things better than I do, Geo, but none of that is doing you any good. You and the wife is gonna have to get together and find out what is the best antenna that she will accept. Do that now, then work on the gear. Put that damn slopbucket rig on ebay. You know thats not what you wanna do.  

Can you do me a favor and repost the photos of your place?

remember, I am not judging you on your domestic situation - it's none of my business. But I'm also not going to sidestep the real issue, and the real issue is that you haven't been able to put a effective antenna in the air for whatever reason.

Maybe after you and her have a convo, you can give us a idea of what she will accept? Then we can all go from there.

Also, have you got a paypal account? I would be willing to kick in some money for a new antenna that would work. But only if it is wife approved and follows accepted practice of being known to get out.
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VE3GZB
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« Reply #33 on: December 07, 2009, 08:47:18 AM »

The antenna that VE3AWA and I set up does work, it's a 40m inverted V and with his Kenwood he got out to Indiana and West Virginia within a few minutes of firing it up.

I put one of the mod xformers to work last night, the ART-13. At first I must have gotten the screen grid leads reversed because it broke into self oscillation, proceeded to generate arcs near the plate RF choke.

I reversed the screen leads from the Xformer and that calmed it down. But I'm still not being heard. From the scope it lookin like it's only about 30% modulation that's happening.

The ham who I went to get CW lessons from yesterday, he loaned me a 40m Xtal from his DX-20. I fired up the DX-35, it ran for a bit then something else blew inside it, something related to the PA.

The KW2000B, I reassembled it. There is just a very faint hint of reception now but still no transmission. So I'm on the right track with this filter. I had a devil of a time trying to resolder the broken wire back to the resonator, the solder just wouldn't stick and it's such a small mass!

So I'm going to ask my boss to order some bandpass resonator from digikey for me, it's cheap and I can retrofit it under the chassis while leaving the mechanical filter still mounted, just disconnected.

73s
geo
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The Slab Bacon
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« Reply #34 on: December 07, 2009, 09:17:14 AM »

Geo,
      this post is not a flame, but it is a boot in the ass to try to get you headed in the right direction. First of all your money is tight, so you have to focus your finances in one direction at a time. Complete one stage at a time.

You have mentioned in a previous post, you are using a homebrew one-tube regen receiver. The first thing you should do is bite the bullet and get yourself a good, descent receiver, so you can at least hear if someone is coming back to you, and figger out what frequency you are operating on. One tube regens are a lot of fun, but as a novelty, and not as your main station receiver!!

Like others have said: Take that defeatist attitude and toss it out the window!! All of us have had our trials,tribulations and bumps in the road to get to the point we are at now. All of us have also gotten lelp and "pointers" from those that we feel know more than we do. All (or at least most) of us have paid our dues to get where we are. One of them was perseveerance! ! ! ! If you read enough of the posts here,
you will start to figure out who does and who doesnt know what they are talking about.

Then decide which path you are going to take with your homebrew TX, and stay on it until you have conquered it!! Dont waste your time building a 10w piss weaker for phone. No one will come back to you if they CANT pull you out of the noise, you will get "squashed like a bug" and trampled over. Remember, it doesnt take that much more time (or money) to build a 100w rig than it does a 10 watter. Again a 10w piss-weaker is more a novelty than something you'll want as your main tx. Especially with current band condx.

Dont spread yourself any thinner than you can afford to (time or money). Stick with your PLANNED path and dont give up until you conquer it!! If you cant get something to work properly, instead of giving up, set it aside and dig out the books, some careful research will usually reveal what YOU've done wrong. The learning curve is more than 1/2 of the fun!

                                                           the Slab Bacon

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G3UUR
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« Reply #35 on: December 07, 2009, 12:57:58 PM »

George,
          Just put a 0.01uF capacitor directly across your Kokusai filter (P to G) and see whether that livens up your KW2000B on receive. If it doesn't, then you have something else wrong with the set. If it does, the filter is clearly the fault.

If the filter is duff, that LTM455DU is totally unsuitable as a replacement because it's 20kHz wide at the -6dB points. The original MF45510CK is +/- 1.0kHz (2kHz total) minimum, and usually measures about 2.6kHz total with up to +/- 0.3kHz centre frequency offset. The carrier crystals were usually matched to individual filters. There is a modification to replace the original filter with a ceramic type CFJ455K5, but this filter requires 2kohm terminations and needs transformers to match the KW2000B input and output impedances. The modification was described in a RadCom article by G3WCE some years back. It's unlikely that your old carrier crystals would be usable with the new filter and you might have to use 455kHz ceramic resonators in place of the quartz crystal ones. This project could get very involved and expensive.

Take the Slab's advice and concentrate on one of the projects you can more easily finish. Forget the KW2000B for the time being, but don't throw it away or scrap it. Save it for another day.

Dave.
   
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Dave,G3UUR
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« Reply #36 on: December 07, 2009, 01:12:22 PM »

George, you may be overdosing on advice by now but I did not realize you had antenna and rx issues -- yes you have to hear people to work them so the receiver and antenna may be higher priority now.

Here's a link to W3JN's page on receivers.  You can get an old National rx for not a lot of money.  Don't forget the newer software defined receivers; some of them are inexpensive and some of the guys here have had good experiences with the SoftRocks (I confess to knowing almost nothing about them though).   You can probably ask about them here and get some answers, and I bet everyone can tell you about the older boat anchor receivers  Cheesy

http://amfone.net/ECSound/JNRECS.html

73
Rob
K5UJ

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The Slab Bacon
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« Reply #37 on: December 07, 2009, 01:23:55 PM »

George, you may be overdosing on advice by now but I did not realize you had antenna and rx issues -- yes you have to hear people to work them so the receiver and antenna may be higher priority now.

Here's a link to W3JN's page on receivers.  You can get an old National rx for not a lot of money.  Don't forget the newer software defined receivers; some of them are inexpensive and some of the guys here have had good experiences with the SoftRocks (I confess to knowing almost nothing about them though).   You can probably ask about them here and get some answers, and I bet everyone can tell you about the older boat anchor receivers  Cheesy
http://amfone.net/ECSound/JNRECS.html
73
Rob
K5UJ


or

http://www.amwindow.org/tech/htm/slabrxreview.htm
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flintstone mop
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« Reply #38 on: December 07, 2009, 03:15:23 PM »

Wished I had a working multimode transceiver to send to you and give that big boost, at this point. Anyone out your way that can let you borrow a rig? Keep for warm storage? The typical 25 watts from a plastic radio won't help your present situation to get on 75M AM at 9PM, but it's a start.
Early eve QSO's are possible with low power. But as DERB mentioned the antenna issue has to be fixed.

Fred
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Fred KC4MOP
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« Reply #39 on: December 07, 2009, 09:56:05 PM »

estimated filter loss of -369 db on rx and tx.  Cheesy

Yea, pretty much!!

Think I have it solved. I've made a temporary patch to bypass the narrow bandpass mechanical filter. Bandwidth is too high as a result but it's now receiving with good sensitivity and transmitting well. I can make the plate ammeter and the SWR meter dance quite nicely now!

The temporary bypass patch? It's a small AM 455kHz IF ceramic filter I salvaged out of my stepdaughter's dead alarm clock! He he!!  Grin

I tried to CQ this evening but there's so much noise, I couldn't tell if I was being replied to. I used the receiver in this KW2000B and my R1155, on both all I could pickup was noise this evening.

I'll try again some other time to make contacts!

For a more permanent patch, I'm going to design an active 455kHz filter to fit inside the original can using low cost ceramic filters and opamps/jfets.

I'm not going to waste time on trying to make this silly mechanical filter come back to life, some ideas (like that one) was just plain awful.

As far as the DX-35 goes, well something died in it last night related to the buffer and final. I looked at the schematic I have and I'm not nuts about the design. What I might do is reuse the sockets, power supply and chassis to make a transmitter of my own design. It does have a nice Pi network in place.

I can take the design of the 6146 rig I've breadboarded on copper board and adapt it to work in the chassis of the DX-35, including a decent built-in VFO too.

The current 6146 rig isn't modulating correctly - I'm suspecting I'm trying to pull too much current on the 500V bus to run both the final and the modulator.

73s
geo
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K1JJ
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« Reply #40 on: December 07, 2009, 11:09:25 PM »

Good going, Geo!

Judging from your last post, I think many of us underestimated your skills there. You did a good job getting to the root of the problem once you focused on it the following days.  You should have no problem getting that rig and the others working on the air.

I think the technical lesson to be learned from that rig is usually there is only one thing wrong... or maybe two - caused by incidental damage from the first.   Unless a hambone got into it and roughed it up badly, crap outs usually are limited to one area.  But not always, like say, a lightning hit... Shocked

Keep posting your projects and progress. I get a kick out of seeing what you're doing with the keen improvising you do there.


BTW, as already said, it's not a simple job to get a new filter working correctly with the carrier oscillator for good  sideband suppression, audio quality, etc. Make the carrier oscillator xtal variable with a trimmer cap and you will be in good shape to align the rig correctly. At least keep this in mind if you run into problems.
 
Later  -

T


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Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

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« Reply #41 on: December 08, 2009, 01:03:26 AM »

George, cleaning up that filter will take more than methyl hydrate. Methyl hydrate is not vigorous  or a strong enough solvent.    You need something like trichloroethane 111 or similar, or at least acetone. Then you have to clean out all the foam debris carefuly so as not to impede the resonance of the  mechanical elements.    It must be clean, clean, clean when done!!!   

But you're on the right track.  Too bad you don't have an 80M antenna.   Put up some bird-houses on 30 foot poles and run an end-fed Zepp, like I did.  It can zig and zag all over creation (like mine did) and you'll get out like a bomb.  With my ziggy-zaggy EFZ I worked the UK  on 80!    Think about it.

A receiver, eh?    I have a basket-case NC-303 here in unknown condition. It's yours if you can get it going.   

I also have some crystals for you for 80 and 40M , including  3645/7290 and  some other real goodies. Let me go see what I have. 
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VE3GZB
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« Reply #42 on: December 08, 2009, 08:42:36 AM »

I'm going to start working on designing a narrow bandpass 455kHz active filter circuit to replace this chunky mechanical nightmare soon. Car suspension should be mechanical, not IF filters.

Ed - If you're ever near Orangeville anytime soon, drop the receiver off and I'll take a look at it for you, see if I can find the root of the problem and fix it for you. I do electronics for a living.

73s
geo
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Ed-VA3ES
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« Reply #43 on: December 08, 2009, 10:25:10 PM »

Ed - If you're ever near Orangeville anytime soon, drop the receiver off and I'll take a look at it for you, see if I can find the root of the problem and fix it for you. I do electronics for a living.
So do I.  Been an electronics and RF technologist for over 35 years.  I could easily fix that receiver, but it's really surplus to my needs, and sitting in the garage.  I was going to get to it eventually, but already have  5 receivers ahead of it!   Grin

Orangeville, eh?    Not likely. I see that you're north of Toronto.  Since I avoid  the GTA like the plague, I'm not likely to be anywhere near Orangeville soon.  We'll try and get  the  '303 over to you via "Boatanchor Pony Express".  Unfortunately, you'll have to deal with the boys from VE3NTH's "Short Skip" - Al, VE3AJM, or Ken, VE3MAW,  who often visit here.  (I know you've had "issues" with them.)
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VE3GZB
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« Reply #44 on: December 08, 2009, 10:31:32 PM »

No worries.

73s
geo
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VE3GZB
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« Reply #45 on: December 09, 2009, 08:42:57 PM »


Can you do me a favor and repost the photos of your place?

Here's a crude drawing I did on the computer showing the antenna as compared to the house (view facing north, antenna is stretched in an East-West direction).

VE3AWA came up and set it up with me, then he hooked his Kenwood up to it and almost immediately made contacts down in Indiana and in West Virginia.

None of the trees on the property are old enough/tall enough, the original trees/house were knocked down by a tornado back in 86.

There is a long clothesline (metal core) which has been slingshot over the top of the TV antenna about 25 feet from the ground, and that clothesline is used to haul up/down the inverted V by a separate insulator.

The tethered ends of the inverted V are tethered to young trees by insulators and more of this clothesline stuff. The tethered ends are about 9 feet from the ground.

RG/58 was used for the install.

Not shown are the villages high voltage 3 phase power lines and Cable TV lines which run directly past the house, in parallel with this antenna. They add wonderful colour to the signals I'm trying to receive, rather like trying to listen to Bach in a slaughterhouse.

73s
geo


* VE3GZB.jpg (51.3 KB, 1024x768 - viewed 484 times.)
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N3DRB The Derb
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« Reply #46 on: December 11, 2009, 04:19:11 PM »

that should do it for you on 40. nothing wrong with that antenna. What's the status on getting something going using your VM-2?  805 final modded by Huh? Do you have plans for a speech amp/ driver?

oh, and what's the antenna tuner that you got?

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VE3GZB
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« Reply #47 on: December 11, 2009, 04:35:07 PM »

I'm working on making the KW2000B get on the air in a finer business. It seems to be kicking out a signal. It's got a built-in tuner too (Pi).

Some ceramic resonators arrives for me today, 455kHz. I'll test them for bandwidth and see if I can fit them into the signal chain.

When I hook it all up I can get better than 1.4:1 SWR and plate current swings up to about 150mA.

That rig came with a KW E-Zee tuner, but the tuner needs a bit of work (dirty connections).

It's been so noisy lately on 40 and 80, so I'm not hearing much, just lots of noise.

The 805 rig? I'm learning CW now so I'm thinking it will make an awesome CW transmitter! It is still together and still runs! I do have most of the parts to start building a big modulator for AM, but it's -20 in the garage - that's where I'd be doing my metalwork.

I don't have final PA tubes for the modulator yet, so I'm waiting until they arrive, then I can start planning a modulator.

73s
geo
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« Reply #48 on: December 11, 2009, 05:17:55 PM »

You're doing good George; got some irons in the fire.  Good to learn CW because then you can send and receive information with the most simple basic transmitter, a RF generator you can key on and off.

I used to think CW wasn't that important anymore but I was thinking of it by itself as a way of transmitting and receiving information.  I now realize it is still important in conjunction with basic homebrewing and learning.  I am starting out just fiddling with AF vacuum tube amplifiers--not much to go wrong.  No RF, no frequency control, no oscillator, just audio stages. Then I'll move on to VFOs.   Knowing CW lets a ham who is trying to avoid becoming an appliance operator learn how to homebrew a RF generator he can key on and off so it is important for learning electronics so a basic rig can be used on the air.

73

Rob
K5UJ
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« Reply #49 on: December 12, 2009, 08:19:56 AM »

The fellow who is tutoring me in CW, he makes regular contacts down to West Virginia on just 1 watt!

And my friend Lou (VE3AWA) worked a VE7 on just 2 watts using a rig he assembled out of vintage British parts!

Now those are the kind of feats I learned of as a youth, and I wish to duplicate! But nobody ever told me that those were accomplished on CW. I naturally thought those could be accomplished on Phone at those power levels.

I'm working towards the goal now, I meet Lou today, he's loaning me another rig, we'll probably do some more CW together, then tomorrow I continue on lessons as well.

73s,
geo
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