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Qrp +


#1

I started chasing in late August of 2012. Most everyone knows, especially in the U.S. , that I have been an all QRP chaser. For my birthday in November, I purchased a KXPA 100 amp to go with my qrp K3. The main reason I did this was I got so frustrated missing out on a lot of the SSB chases.
Still going to use QRP for the CW chasing . If I don’t need the filtering that the K3 can offer, then about 50% of the time I use my MTR 3 bander or my HB1B for CW chasing. CW gets the job done . Best bang for the buck ! Also I’ve heard several SSB conversations I would like to join in on on 40 mtrs in the evening. They can barely hear me with the qrn sometimes , but now they do at 80 or 100 Watts pep.
So if someone hears me on SSB and says … Scotty can’t be QRP. They’re right. Now , if need be, I’ll be QRO @ 40,60,80, or 100 watts. Hi !
I know a better antenna than a 44 foot doublet is the better answer, but not going to dig in frozen ground for a tower base in the winter. Maybe a hex beam next year.
Till then 72 and 73 to all ! de Scotty KG3W


#2

Enjoy your new-found prowess Scotty! I second the motion for a hex beam in the spring.

73, Barry N1EU


#3

I’m fighting the urge to buy a KXPA-100. But I keep getting decent reports with the KX-3 on CW. SSB?
I do have a mike some place, but don’t tell my friends.


#4

The best thing I ever did was to build a hex beam which changed the world. If I had the money would buy a KXP-100 as well.
With these solar flares things get a bit tough at times. Think another homebrew project will be on the way.

73’s, Nick


#5

Good luck Scotty.
I agree with @N1EU and @VK2AOH
My 6 band hexbeam has been up since September 2013 - best antenna I have ever used. Pic on QRZ.
Night night in UK :wink:
Mike


#6

rgr portable amplifiers like the KXP-100. From an activators POV this is my next approach.

Under construction … Built into an old CB amplifier case that is ideal for the job. Its more compact then the KXP-100 and wont require all the RJ interface cabling, I am purely doing this for fun as usual.

A micro sits under the LPF PCB to interface to the KX3 to read band change data, selects one out of the four filters to use on the appropriate band. It also handles the T/R switching. Delivers around 140W from 11W of drive… Amplifier design is Based on http://www.mikrocontroller.net/attachment/241464/an762.pdf which was further modernized by G6ALU http://www.radio-kits.co.uk/radio-related/150W_PA/150w_PA.htm.

Transistor types required are a fairly loose specification, HF12-100’s from spectrum devices are probably the best and are amazingly robust.

LPF’s and the KX3 interface software is my own work

Current project for when the SFI goes really south. :blush:

I am all for QRP on the summit, but sometimes you need a bit more welly.

Jonathan


#7

Definitely a beam antenna is IMO something to have before a power amplifier.
A beam antenna will let you hear many signals that you won’t even feel with antennas like a dipole or a LW for instance.
If you can’t hear somebody you will never be able to have a QSO with him/her, no matter the power you can use.
However, I agree that 100 watts will make things easier for you on 40/80m.
Good luck and best 73 de Guru


#8

Wow, Scotty I wont know what to do if I don’t have to search the aether at the end of the pileup for your certain presence.
Cap
W0CCA


#9

It’s been very helpful so far Barry. Tnx


#10

I’ll tell you John; The few times that I tried the amp on SSB , it’s worth it. I still try with 10 watts first though.


#11

My CW chasing is easy because of the fantastic ears that you activators have. You do and awesome job !


#12

I used to have a 3 element Cushcraft A3 , back in 1982. It did make a super difference. Before that I was running a wire up in my attic. It was like a night and day experience. Ah the old novice and general days. I was using a loaned setup. Heathkit DX 60b and seperate vfo. The receiver was a Hallicrafters HQ 170. Used a ceramic knife switch to go back and forth from transmit and receive. Only 35 watts CW but the bands were on and 11 year high then.


#13

Good luck with your amp Jonathan.


#14

Hi Scotty,
Good to hear you will continue to use QRP to chase when possible. It’s worth remembering that a lot of the SOTA chasers hold foundation (or equivalent in other countries) licences and are limited to 10w in any case and it’s worth asking what antennas and other equipment they have to get over the barrier of the pile-ups of QRO chasers (I admit it, I being one of them with 300w).
It’s interesting that the most common answer seems to be patience, keep trying and wait until the pile-up dies down, hoping the activator will still be there. The other item is to have as good an antenna as possible for the space and money available and indeed the Hexbeam appears to be a common choice as well, along with full wavelength loops - either will give gain over a dipole. Some do love CW and indeed it’s easier to get a CW signal through than an SSB one but coming back to SSB, good RF speech clipping/compressing is a great help. I use this both from the home QTH and when activating (the majority of my activating is with 5w SSB from the FT817). I have had several people say that my signal appears louder than it should compared to what the S-meter says and this is purely down to the RF clipping on the audio (audio is taken to 455KHz clipped and then brought down to audio again - in proncipal this reduces the chance of splatter created by simple audio compression). I’d say the ability to get through with just 5w SSB when using such a clipper is increased by at least the equivalent of a 3db increase in power.

73 Ed DD5LP


#15

Morning folks

Been chasing sota,s since Sept last year. And as Ed says some of us are only 10w stations by our licence such as I am. Only had wire antennas of various types including portable and I do alight.

Lot of skills have been learnt in that time again as Ed says. But feel the best one i feel is expect the unexpected like yesterday me friend in Norway says hmm bad K and A index etc low sunspot numbers against us. Yet being a Monday the activators were out in force and conditions not bad as managed 70 odd pints on 11 summits yesterday plus bonus season helps with people doing the bigger summits because of.

Doing the 10m and 6m challenge is a real challenge at moment due to winter conditions up here yet still tune in just in case signals just might appear.

But end of day because you don’t have a bloody great antenna system or the wattage or just cause you have a very simple system does not mean you can catch some decent DX. Radio is like fishing some days you get a cold, some days you can’t put the rod down to have a cuppa tea because its so busy.

Finally, done a lot of radio via 11m CB and now ham of course with out the AMP feel don’t need it dirty Horrible things As best comment I have heard is if you can’t hear it you no making the trip with not matter what you have. If conditions are not there it ain’t happening plus less likely to cause QRM to others and also found beams are good way to go if you can put one up. And hex beams certainly are well praised by many I know that have them. And best laugh there an wire antenna too.

Karl


#16

Scotty, I’m even more pleased about our QSO a few weeks ago, didn’t know that you were QRP also! I was using my new MTR-5B. Not sure about my power level, but I’m guessing at around 4w.

I once ran a borrowed FT857 on an activation for SSB but I was a bit shocked at the power requirements for that beast! I was given a FT101 a while ago for spares (never applied power to it!) but otherwise I’ve never owned a non-QRP radio in my 18 years as a ham.

73, Colin M1BUU


#17

Scott,

I have recently acquired a 2nd hand Tokyo Hy-Power HL-50b in pretty good shape.
I do not much chasing from my QTH, but it has made a significant difference on how quickly I get through and helped specially with SSB.

A beam or steerable dipole “in the high” will make a big difference on what you hear as stated above (day and night). Over the last 2 weeks, I have used a fixed 20, 15 & 10m dipoles at 11m on a Spiderbeam HD glass-fibre mast and what a change w.r.t the lower wires that pick up all the man made noise from the houses nearby in the city. 6hrs of CQ WW CW with the little amp (50W) and my G11 SDR delivered 67 DXCCs and 22 CQ zones, 6 Continents (with the help of super antennas on the other end…!)
A homebrew Cobwebb and 15m steerable monoband Moxon are in the planning stage.

Enjoy your KXPA 100 amp, and if you have the space to fit the Hex, go for it!

The amplifier and a heavy 7Ah SLAB and a set of dipoles 40-10m will travel with me on the more accessible summits activations in EA2 & EA5 over the Christmas break.

73 de Angel M0HDF


#18

Hi Karl,
All antenna are wire just different dimensions/configurations. The big SteppIR antennas are wire but just configured as metal tape so they can be rolled :laughing: :laughing:
Night night
Mike


#19

on the subject of amplifiers, the HF Packer amp is a compact 50w HF amplifier available as a kit from HFprojects.com in the USA. All who build and use it are complimentary. Another on my wish list.

It does not seem to be mentioned here as an amplifier option but looks to be a good candidate for home and field use.

Andrew
vk1da/2uh


#20

I am interested and emailed but no response. Anyone know if it is still available?
73,
Rod