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Author Topic: A call to kit designers for a small portable CW QRO rig.  (Read 4182 times)

gil

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A call to kit designers for a small portable CW QRO rig.
« on: October 03, 2014, 12:46:26 PM »
I love QRP CW rigs, built most of them and still own a few. There is however a type of CW radio I have not seen, a CW-only simple 100W transceiver. It would be single or dual band, with built-in keyer, maybe a DDS VFO. Not just to have something new and interesting to build, but because it would make a great emergency radio. I would want it as small as possible, with a LED display (three digits?), tuning and volume knob, and a function button. That's it! 100W CW is like 2kW SSB! Without the current draw of a big amp.. Sure, it would not operate as long as say, my K1, but there are many circumstances where a vehicle's battery might be available, and when you absolutely need to make contact, there is nothing better than CW. Mr Steve Weber, please? Any designers interested?

If there was such a transceiver available I would buy two! A 20m and 40m version, to take sailing, as safety gear on top of the regular EPIRB. A marine SSB radio costs almost $2K, and a tuner $500, which I can't afford..

Anyone else would want something like that? What would you use it for?

Gil.

RadioRay

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #1 on: October 03, 2014, 01:34:12 PM »
I'd go for that in a BIG way!  If people say that there is no market, then they need to look on E-Bay where 35+ year old CW only Ten Tec like the Century 21 & 22 radios still sell quickly for more than they cost new.  Frankly, 25 Watts is only 1 S-unit less than 100 Watts on receive, so I'd go for that rather than 100 Watt, but I'd be happy either way.  Class "C" amplifier or maybe class "E" so that efficiencies are very high and amplifier idle current is minimal. Circuits OPTIMISED for CW are far an above those optimised for wiiiide SSB voice with CW thrown-in as an after thought.

I specifically do NOT want all the extra complication and current drain for SSB, because I do not use it except for one net check-in per week, to support a friend. I operate 99.9% CW because it's so effective and frankly, it's less noise and more communication.


Good Idea Gil!


73 de RadioRay  ..._  ._
"When we cannot do the good we would, we must be ready to do the good we can."  ~ Matthew Henry

gil

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #2 on: October 03, 2014, 01:59:00 PM »
Quote
If people say that there is no market, then they need to look on E-Bay where 35+ year old CW only Ten Tec like the Century 21 & 22 radios still sell quickly for more than they cost new.

I was looking at a Drake 2-NT but that is a transmitter only and the problem with tubes is that you need high voltage, which on a boat isn't the smartest thing to do...

Maybe a simple design schematic can be coupled with a simple amp design on the same PCB. Add a watertight Hammond cast aluminum case and you're in business!

I'd even take a crystal controlled rig...

Gil.

cockpitbob

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #3 on: October 03, 2014, 03:58:17 PM »
Why not your favorite QRP rig (AT-Sprint?) plus an amp?
You've got QRP when you don't have a power supply and QRO when you do.  This one on eBay is just the right size and power for me (6"x4"x1.4", 45W).  I'd question the quality at that price.  Here's a bigger one on Amazon that gets great reviews.

KK0G

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #4 on: October 03, 2014, 04:04:24 PM »
Gil, other than the fact it's not single or dual band, and that it has a few more controls than just a VFO, AF Gain, and function button, you pretty much just described the Elecraft K2/100.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

gil

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #5 on: October 03, 2014, 07:53:11 PM »
Quote
Elecraft K2/100

Certainly, I did think about it.. My only reservation would be the cost...

Gil.

KK0G

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #6 on: October 03, 2014, 08:05:27 PM »
Quote
Elecraft K2/100

Certainly, I did think about it.. My only reservation would be the cost...

Gil.

Oh, well you didn't mention that ;D . Yes, the K2/100 would not be a cheap option but for what you described it's the only option I'm aware of.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

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RadioRay

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #7 on: October 03, 2014, 09:27:38 PM »
These days, for CW only, a DDS into an amplifier chain with appropriate bandpass filters would take care of the CW transmission.  The keying portion between the buffer and first amplifier step can be made to smooth the leading and trailing edges slightly to eliminate the key clicks/initial generation of sidebands during the ON/OFF transitions.

Receivers can run the gamut from modern direct conversion with audio filtering to conventional single conversion superhet with IF filtering or maybe even an SDR'like hardware phasing approach with filtering like the MicroR2 receiver.  I'd be tempted to make an up to date version of the old Ten Tec Century 21, using modern parts and make it smaller and field friendly. If the radio is a half pound with a low drain receiver, then even a two 1/2 pound battery is not a problem, folding solar panel and viola!  you're QRO capable without all of that rubbish needed for voice.

You know - it's MUCH more pleasant discussing these things here, rather than on the hobby ham forums, where the place is filled with trolls who need an attitude adjustment.  I mean REALLY - Don't they know that WE ARE THE EXPERTS?!?!? Wazz-up Wi DAT???   moo-ha-ha !   Seriously though, it's amazing how many soreheads there are who buy a station and have no idea how to operate that series of expensive boxes and why it's important.  Fortunately, they are rarely on CW except for their damned contests... and then usually using computer Morse which is pretty poor compared to the human ear.



"When we cannot do the good we would, we must be ready to do the good we can."  ~ Matthew Henry

Lamewolf

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #8 on: October 04, 2014, 09:03:17 AM »
I have 2 old Yaesu FT747GX radios that are in super good shape and I turned one of them into a field radio.  The 747's have a plastic case and are fairly lightweight 100 watt rigs, but on the one I converted to a field rig, I set it internally to a maximum output of 30 watts, and swapped out the dial and meter lamps with super bright LEDs to save a little bit of battery power.  The 747 also has a 500 hz CW filter built in, so it make a good CW rig and I also added a small PIC based keyer to the rig.  It will operate for several hours on a 12 volt 18aH gel cell battery and I use an old Heathkit QRP tuner with it that is rated to handle 50 watts.  The 747 will do AM and FM, SSB, and CW and with the addition of a laptop and small interface will also do the digital modes.  Currently I am putting together an all band vertical half rombic for it that requires no tuner for 10 thru 160 meter operation.  This will all go in a backpack along with a solar panel for charging the battery but will not include the laptop and interface because most of my operations will be CW.

gil

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #9 on: October 04, 2014, 04:54:10 PM »
Quote
This one on eBay is just the right size and power for me (6"x4"x1.4", 45W).  I'd question the quality at that price.  Here's a bigger one on Amazon that gets great reviews.

Thanks for the links Bob. That might be an option, though I do not like having connecting wires everywhere.. Maybe if I put everything in one box with a QRO tuner.. But then it becomes a size problem.

Maybe the solution would be to buy a small amp and install a small CW radio inside the case.. I'm not very confident about RM-Italy... I'll go read those reviews, try to see if any are from real Ham operators, not CBers who would not necessarily know how to evaluate it.

I do want something that would only occasionally be used for semi-emergencies while sailing. I will have a DeLorme InReach (http://www.inreachdelorme.com/) in case the boat goes down..

Gil.

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Re: A call to kit designers for a small portable CW QRO rig.
« Reply #9 on: October 04, 2014, 04:54:10 PM »