New QRP Labs 5W CW Transceiver Kit.

[cockpitbob]

Meh, the 5 toroids to wind doesn't look too daunting.

I just downloaded the assembly/user's manual.  137 pages!!!  It's very nicely done!  This is clearly a labor of love.

It has power consumption curves for Rx and Tx for the various bands.  Rx is a little high at 130mA.  The backlight current is 15mA, so running that through a switch could save a little.  But then, with a battery pack of three 3,000mAh Li-ion batteries, it will run this thing in Rx for 23 hours.  That's plenty of operating time.

Tx power and current are about the same for all bands:
5.0W   @ 15V,     520mA  65% efficiency
4.25W @ 13.8V,  475mA  65% efficiency
2.75W @ 11V,     400mA  63% efficiency
1.75W @ 9V,       350mA  56% efficiency
1.0W   @ 7.5V    300mA   44% efficiency

It looks pretty bullet-proof since it's rated for operating from a 7V - 16V power supply.  That's a really wide range.  I like that it will operate down to below the voltage of a discharged 3 Li-ion pack (about 7.5V).  I get to use the whole pack.

There's so much information in the manual that I can tell I'm going to learn a lot about radio circuit design :D

[cockpitbob]

NEXT KIT TO SHIP
    serial number
   184
:P

[caulktel]

I just finished reading the circuit description in the manual, wow! Hans has really thought this radio out, in fact there are a lot of features for the price. I really like the class E final amp. A couple of years ago I built the NM0S NS-40 CW transmitter which is also class E amp and very efficient, 5 watts out of a IRF-510 that runs cool without a heat sink. I'm kind of surprised Hans didn't one Mosfet vs three of the smaller BS-170's. Anyway, this is going to be a cool radio. Building in the tools to balance the I/Q phase is a nice touch too. All for 51 bucks:-)

Joel
N6ALT

[swxx]

I think backlight is as much as 35mA. There is this suggestion too aside from switch:

Modern LEDs as used in today's LCD displays will provide fairly bright
illumination at currents of 3 to 10 ma.  Try using a larger resistance
value in series with the backlight LED.  Usually 1K in series with a 5V
or 2.2K with 12 volt source is adequate for both day and night viewing.
Experiment to see what is best for your particular situation.

Also this can be made dual band (not instant switch over, but still...) without too much trouble, here regarding 20/30m:

You won't be able to use the band pass filter T1 on either band. It is single band because it is quite sharp (see spectrum analyser traces in the manual). You could probably find a number of turns for the tuned winding of T1, which allowed the trimmer capacitor to tune for either 20m or 30m. Measured tuning ranges are also published in the manual. BUT, it would mean that when you want to change band, you would need to re-peak the BPF each time using the self-alignment menu item "8.7 Peak BPF".

You could build the LPF for 20m and operate 30m into it but you may not achieve adequate harmonic suppression on 30m band.

The Class-E resonant circuit is quite broad and you could find a compromise-value, it would probably result in a little loss of efficiency and power, but may be acceptable.

[gil]

I'm kind of surprised Hans didn't one Mosfet vs three of the smaller BS-170's.

Steve Weber uses the same scheme for his MTR series. I bet that's where he got the idea...

Gil.

[cockpitbob]

NEXT KIT TO SHIP - Still
    serial number
   184
No change in 4 days :P

[swxx]

These are being shipped from China so I wonder what the situation there is. If your number is 493+ then that's in the second batch which is allegedly in 2 weeks time. How many are in that batch? One would hope 500 otherwise we're in trouble.

The rate at first was averaging 10 sent out per day, but that was a small time sample so no good indication of longer term. If it is, and now it has dropped way below that average, we won't get our QCX this year. So they certainly need large quantities AND full time sending out, which I don't know how that can be afforded easily even in China.

I think the better option if they can arrange it, is to have this done across the border in Laos. The postage is crazy cheap, and the cost of living is less. That's how some of the Pixies are sent out.

[caulktel]

Sparks and all,

QRP Labs was on Yahoo groups, but has move the group to https://groups.io/g/QRPLabs

Good move in my opinion.

Joel
N6ALT

[cockpitbob]

I got the email that my kit shipped yesterday
The email asks that I email them when it arrives so they can track shipping time statistics.  I like these guys.



NEXT KIT TO SHIP
    serial number
   318

[caulktel]

These are being shipped from China so I wonder what the situation there is. If your number is 493+ then that's in the second batch which is allegedly in 2 weeks time. How many are in that batch? One would hope 500 otherwise we're in trouble.

The rate at first was averaging 10 sent out per day, but that was a small time sample so no good indication of longer term. If it is, and now it has dropped way below that average, we won't get our QCX this year. So they certainly need large quantities AND full time sending out, which I don't know how that can be afforded easily even in China.

I think the better option if they can arrange it, is to have this done across the border in Laos. The postage is crazy cheap, and the cost of living is less. That's how some of the Pixies are sent out.

Actually, they are being shipped from Tokyo Japan.

Joel
N6ALT

[gil]

Mine shipped too but nothing so far...
Gil

Sent from my SM-G928F using Tapatalk

[caulktel]

Mine is going to be a while, number 628.

Joel
N6ALT

[gil]

Christmas... 2019...
Gil

Sent from my SM-G928F using Tapatalk

[cockpitbob]

I just got a box from Tokyo 8) 8) 8) 8) 8) 8) 8)

Lately I've been working my a$$ off nights and weekends.  I think I'll take some time for myself this weekend and build it (even though I have an un-built Frog Sounds and a Pixie that needs debugging.)



NEXT KIT TO SHIP
    serial number
   506

[caulktel]

Congratulations Bob,

I hope you enjoy building it. Mine will be awhile yet, but that's okay I'm in no hurry. I think I'm going to mount the display and all controls off board so I can put it in a nice case later.

Joel
N6ALT