NEW CHA F-LOOP 2.0 from Chameleon Antenna is NOW AVAILABLE!

Hi Julian,
I accept your comments, except that I am not selling the loop and have no financial interest in it. The info on my site is for archive purposes only. You make some good points. I have apologized to Carl- and now also to you. My behavior has been less than what I demand of myself.
Thank you for your comments,

Dale W4OP

 

I think we could use the wsprlite and dxplorer website, but that would require all competing loops to be in the same place at the same time, each with its own wsprlite device. Then results can be compared on the dxeplorer website.
I like very much the idea of using wspr as one point of measure.

Still performance is only one point to measure. In fact we already know the W4OP will perform better on 40 than the F-LOOP since it is physically larger than the F-LOOP. The F-LOOPs larger Booster kit (Main loop and Coil) should also be mesured since Dale/LNR insist the W4OP is the most efficient loop available commercially today.
There are other perimeters which detrmine overall, if I loop is a good useable product, not just an aligator with big teeth.
I think we should look at
- Manufacturing quality
- Weight
- Breakdown size
- Portability
- Set-up & tear down time
- Robustness
- Total cost vs what you get.
Each given a rating of one to 5 stars
Any others?

Julian

 

Hi Dale
I don't need an apology and don't role that way. Didn't take any of this personally so no worries. The thing I try to accomplish is sorting through all the marketing mess and misinformation put out by companies and their proxies.
For me it doesn't matter which loop is better or worse, or a compromise here, but better there. What matters is the amateur radio community gets the right information. I have not looked at your website yet, but if those bold claims are still there, then one could say yours was an empty apology.

Nevertheless, your apology is accepted. I am still going to acquire a W4OP loop at some point to put yours and LNR claims to the test. Then give it away on my channel or donate it to a deserving club.
kind regards
Julian

 

Julian,
If you want to email me privately (QRZ address is fine), we can excahnge some thoughts on antenna testing- there are some pitfalls and I have done this professionally.

Dale W4OP

 

The funny thing about this thread is, yesterday after the frustration of reading how heartless ham radio manufacturers can be to one another, I needed to wind down. So I went outside to the patio with my 817 and one of the loops which doesn't work. I had a very nice 2.5w psk31 QSO into italy.
That's not uncommon, but that "first time" feeling you get after doing something people tell you isn't possible with the gear you have yet, I do it almost every day, Digital QRP! The proof is right there, even if everyone says no.
Julian

 

I have both the F-Loop and P-Loop v2.o and they work great. I have made dozens of videos on YouTube showing these antennas in use. If you are looking for a quality HF antenna with a low profile that does not involve throwing water bottles, hammers, wrenches with strings over tree limbs - then then try a loop antenna. I have operated off of decks, inside cabins, in the field with these antennas with no problems. My one recommendation would be to buy extra Velcro straps for your kit - they are easily lost in the field. I purchased extra straps in bring colors and they work great.

 

And hallelujah and a big amen that this is over!

 

Hell I'd like to acquire a loop for testing too!!! My QRZ address is good also!! Just FYI... y'all probably will not get it back!!!

 

Would you please post a link to your channel or playlist? I like to share videos from other operators using similar or the same equipment that I have.
Thanks
Julian

 

Agreed!
It could take a few months to save up the pennies to get the W4OP loop here for field testing. Then we can come back to this topic, taking them out in the field where it matters. Also do it without abusing one manufacturer or the other.

Julian

 

Julian, here is a webpage showing the results of what I term "comparative antenna testing" where the accrued WSPR SNR data from the two antennas under test as received at various spotter stations were plotted. The two antennas under test were excited simultaneously (this works to offset varying ionospheric conditions that affect propagation over time) with WSPR signals from two transmitters separated in frequency by about 100 Hz or so in the WSPR band :

http://www.qsl.net/w/wb5wpa//EHantenna/EH_Mark_2_Vert/

Just two quick examples of data plots :


The K9AN station is 1086 km at 42 deg AZ from transmitting station WB5WPA

and :


DK6UG at 8225 km and 41 deg AZ from transmitting station


I won't go into details how all this was accomplished (or what caveats should be observed on several fronts), as that would be too big a diversion on this thread.

Jim

 

Julian, those are a good start for evaluating a "turn key" commercial product that targets a particular user (or product) demographic. Most of the work I've done the last few years has been in the vein of "proof of concept" evaluation of various 'raw' antenna types like the EH (and spin-offs), the DLM (by Robert Vincent), various loops etc. where final 'form factor' and beauty is not a design or targeted consideration!

Quickie lash-ups like this design that used cheap 17 ga (.045 inch) AL wire, 10 inches of 1 and 5/8 inch Andrews Heliax tie-wrapped to some locally-grown cane (bamboo) poles :



Jim

 

Thanks for the feedback Jim.
On the bench is a WSPRlite and idea for testing. The test methodology was recently validated by Richard @ SOTABeams in his blog "Testing a Test Methodology"
That article can be read here.
This type of testing methodology is attractive as it allows "Joe Average" radio operator to get out in the field to replicate tests, with minimal gear and investment. More data from more sources can validate or perhaps invalidate claims based on what might've been erroneous modelling to begin with.
Awesome point Jim. I'm right there with you.

Julian
.

 

Sometimes I can't tell if my friend and big crazy neighbor Jim is making a joke or not (j/k about that "crazy" part )

As you may recall, I did model it, but I'll be darned if I can find the saved results. If memory serves, recall that it matched up well with all that data we took on 160 M and 80 M WSPR. ) It was a capable antenna that took advantage of that handy r^4function of loop radius vs. loss, and ended up at only a negative few dBi - very impressive for such a relatively small antenna, especially on 160 M

We may have disagreed on this part however, the originating idea on the edginton website about some mysterious "new loop excitation method" was mostly wrong IOW, the loop works well!, but because of our r^4 friend in the loss equation, not some mysterious new configuration.

For me, I recall 2 "bottom lines" - 1) is that it pays to think about mid-sized loops that gave Jim a pretty nice 160 M and 80 M footprint from a small antenna - and - 2) "model this" worked out quite well - although it took a fair amount of time a forum bandwidth to resolve the extreme common-mode issues with the measurement...


Although the highly imbalanced feed on Jim's (old?) loop was at first tricky to get the measurement to match up to the model, in the end, it matched quite well - as it ALWAYS does when the details are properly accounted for ---- including as discussed on this thread above, the use of ALUMINUM for the loop material as instead of copper for the STL's / mag loops ....

 

I'm very tempted to try it the setup time is so fast especially compared to my Buddipole.

Ian