PA0RDT Mini Whip ? Users ?

[bearcatrp]

While listening to ATC on HF out of new york last night. Was able to listen to both sides of the transmissions. Decided to try my wire. Could barely hear ATC. Put the new antenna on. Was able to listen to both sides again. Am recommending this antenna. It pulls in the frequencies better than my wire.

 

[zoofer]

I looked at purchasing the PA0RDT Mini Whip a few years ago but went the amplified loop route instead and was quite pleased with its performance. I'm now ready to get a mini whip after reading up on it. I sent an email to Roelof asking about pricing and availability. Here is his response (by the way I do live in the USA):

The cost used to be 60 Euro, 39 Euro for the antenna and 21 Euro for shipping by PostNL. This amounts to about 70 USD. Delivery time after payment was about 10 business days.

However, due to the changed US tariff policy, PostNL shipment has grinded to a halt and the only option is DHL Express, delivery next business day.
Total cost including tariff and DHL handling fee will be about 130 - 140 USD, which is insane, if you ask me.

If and when this situation will change for the better, I don't know.

73,
Roelof Bakker, pa0rdt

So there we are. As much as I would like to get a mini whip direct from Roelof, I can't justify the crazy shipping cost. So have any radioreference.com users obtained one via ebay or elsewhere and been satisfied with its performance? I'm not crazy about getting a Chinese knockoff, so maybe you know of a reliable alternative source for getting one that's going to work. All suggestions appreciated. And please, no political commentary about tariffs. I think we are all aware of why this happened and we don't need this thread polluted.

Kevin, W4KCA

 

[bearcatrp]

That sucks. Wait until europe pulls its head out of its butt and order one. You will like it. Its worth the wait.

 

[ka3jjz]

Kevin plans are out there for this antenna why not build it yourself? If you have a well stocked junkbox you might have almost all you need

Mike

 

[ka3jjz]

If these antennas are mounted properly they may be a way to go to avoid HOA nazis and the like. But it does take some effort to mount it correctly. Even the one used at the University of Twente (likely the best known public user of this antenna) is well grounded to a metal roof. They should also be mounted as far as you can from the home. There is an article from SWLing.com that is in the early stages of this thread that details this. These antennas are not likely to work very well indoors. An amplified loop (i.e. W6LVP) is a much better bet in these cases

Mike

 

[zoofer]

Kevin plans are out there for this antenna why not build it yourself? If you have a well stocked junkbox you might have almost all you need

Mike

Actually Mike, I may have purchased one of the mini whip kits years ago and just never got around to putting it together. It's in a small plastic bag mixed in with my connectors and cables. But since we just moved it may be a while before it makes an appearance. But I'll keep an eye out for it for sure.

 

[bearcatrp]

When I emailed the guy who makes this about grounding, he said not needed unless in a high RF environment. Mine works fine with no grounding.

 

[dlwtrunked]

That sucks. Wait until europe pulls its head out of its butt and order one. You will like it. Its worth the wait.

Europe has not much to do with it. The shipping cost is mostly the tariffs by the U.S. This is where the tariffs are charged--in the shipping costs. One has to be very careful in ordering anything overseas now as often the tariffs in the shipping costs are not noted and one gets a big surprise in the final bill.

 

[zoofer]

Europe has not much to do with it. The shipping cost is mostly the tariffs by the U.S. This is where the tariffs are charged--in the shipping costs. One has to be very careful in ordering anything overseas now as often the tariffs in the shipping costs are not noted and one gets a big surprise in the final bill.

Actually it's the European post offices current inability to adapt to the new US tariff rules that ended the 'de minimis' exemption for packages under $800, which now require duties to be paid. European postal systems are working to develop systems that adapt to the new US rules. Once those systems are in place, shipping services are expected to resume.

 

[radar_hunter]

So there we are. As much as I would like to get a mini whip direct from Roelof, I can't justify the crazy shipping cost. So have any radioreference.com users obtained one via ebay or elsewhere and been satisfied with its performance? I'm not crazy about getting a Chinese knockoff, so maybe you know of a reliable alternative source for getting one that's going to work. All suggestions appreciated. And please, no political commentary about tariffs. I think we are all aware of why this happened and we don't need this thread polluted.

Kevin, W4KCA

I have a few Chinese miniwhip antennas, advertised as having either "PA0RDT" or "PA0NHC" design.

They all work well from mid-VLF to 20 MHz, but above 20 MHz all of them lose their performance.

I'm not sure if this is inherent to this kind of antenna or if the Chinese antennas just have a compromised design.

However, PA0NHC has measured his antenna design and verified that it can work up to 100 MHz or so. And I know that at least one of my antennas has "PA0NHC modernized design with modern components". Looking at the schematic shows a type of transistor in the final stage (current amplification) which is not really designed for RF use. I'm not sure if it should still work at 20...30 MHz but it is suspicious, and it's definitely not part of the original design.

I tried to measure the antenna with NanoVNA but my results were inconclusive. Removing the input choke did not seem to improve performance a lot either.

It is clear that many, if not most, Chinese miniwhip antennas are not made according to the original design that they advertise. I'm still not sure if the original designs would work better or not. I'd have to test it to be sure. If you want a miniwhip with original design, you have to build one yourself or buy one from the person who actually designed it. If you buy one from eBay, you will likely get a decent antenna up to 20 MHz anyway.

And please remember that a miniwhip antenna must be installed properly to get good performance. Common-mode noise suppression is likely needed. A common-mode choke is often recommended but I've found out that a transformer balun (isolating) works well. The power supply must be good. A switching one may produce noise so a linear or unregulated is better. Sometimes you may even have to use a battery if your mains is dirty.

 

[ka3jjz]

A lot of that can be mitigated to a degree with an amplified loop Those chinese knock offs should be stripped for parts. Yes a loop is more expensive but a lot of the set up for a miniwhip is simply not needed with a mag loop. You don't need to mount them high - in fact if you are interested in MW DX keeping them nice and close to the ground will help with nulling stations you don't want to hear. Same if you do LW DXing. A common mode choke isn't a bad idea here either. The W6LVP antennas are produced here, so no tariff issues. And a big plus is noise reduction - loops are much less sensitive to it. A lot of people have found success with the very inexpensive MLA-30 plus loop. In fact there's even a FB page devoted to tinkerers improving its performance.

Pardon Our Interruption...

Mike

 

[ka3jjz]

The link goes to eBay....why it lists as "pardon our interruption' I have no clue. They take PayPal

Mike

 

[ka3jjz]

More expensive but available via Amazon....

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Buy K-480WLA Portable Shortwave Radio Active Loop Antenna 0.5MHz-500MHz Full Band Radio Antenna LW/MW/SW/FM/VHF/HF/Air 6 Meters 30dBi SDR Ham Radio Antenna with 1800mAh Battery（10 Meters Feeder）: Radio Antennas - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

tinyurl.com

Mike