HF radio: limitations of a low-cost approach

There is a lot of merit in buying later model stuff, the older the radio the more chance of it failing and if it does fail; then the availability of spare parts that will more then likely be secondhand.

Most older HF gear have had a hard life.

Later model radio's receive and transmit better, have more user features like selcall (a must), option of a telephone interconnect and antenna auto tune abilities.

The other big plus is most a computer programmable making it easier to add frequencies as needed.

HF radio's hold there value very well and the newer the radio the quicker and at a higher price it will sell for.

Most of the time we monitor only one channel.

Robin, perhaps we could also add that with multitap it is not necessary to select specific tappings for reception, only for transmission, which is satisfactory for scanning.

As you say, the multitap antenna is more reliable but is a little less convenient than an autotune. But it can even double as a dune flag mast!

Good points Allan

For my backup I just carry 2 30ft pieces of pvc covered wire, attaching one to each side of the coax - even when these are rolled out poorly along the ground to make a crummy 1/2 wave dipole it usually betters the multitap.

Yes Robin, I also carry a length of cable attached to a cord and weight to use as an emergency longline antenna. However, nowadays I consider the HF and VKS737 useful for information and assistance in such matters as obtaining and delivering spares. For life & death emergency I rely on the satphone and carry comprehensive emergency phone number list.

Yagon

What Robin said makes sense on the practicality side.

However I would like to highlight one issue with it. Having in your possession a radio that will transmit on a frequency that you are not licensed to use can be illegal. If this concerns you then you should investigate it.

Phil

Re tap antenna mounting query below - I had an crystal controlled Tracker Scout HF years back with a Lencom tap antenna (beautiful quality comms, but no selcall). The tap antennas have a small base given the height and weight of the rod overall, so they can exert a lot of leverage on their mounting. IMV, a HD spring base is essential and that needs to be bolted to a well mounted steel flange.

You may find this instruction brochure from Barrett useful.

Yagon,

Don't have any digital images that I could show you.

We used to mount them on the passenger side of bullbar, where you could "monitor" where the tip was, in relation to trees, overhead wires or gate caps. And they weren't in the driver's direct vision either.

Have seen them mounted on head rail, up behind the cab, or even on rear spare wheel carrier. The latter position might be a bit close to body work, unless it was on a raised mount. The standard heavy-duty spring mount is very robust, and haven't seen many break. Some do lose the tension in the spring, and tend to "flop" about, even coming back to wack the cab, in really rough conditions.

We used the 4' whips, because we had areas of low gidgea scrub, and were often off road. Otherwise the 6' whips might give slightly better performance. Terlin makes one that is in 2 pieces, though i don't know what they are like.

We used RFI aerials, but didn't notice them on their website now.Check out TERLIN, from WA, for a good variety.

Just on radios again. We have a Codan 8525 that my wife won in a RFDS raffle, and it has been a really good unit. However, at over 25 years old, it mightn't be the one you need, if you could afford something newer.

Bob.

Bob, As you say, mounting location and height can be an issue. Our tapped whip is in the bull-bar, LHS. We are often on bush tracks with overhanging branches that give the antenna some hard whacks, so in this situation I tie the whip back to the roof-rack with an occy-strap. Seems to still have reasonable reception in this mode but have not tried transmitting whilst tied-back.

It is also possible to get the tap-selecting wandering lead hooked in passing foliage and rip it off. Had it happen only once but, even though it was closely wrapped around the antenna. Ripped a few other things off that trip!!

Also found that the HF antenna and the dune-flag mast banged together when rolling across tracks such as the Simpson. Now they are on opposite sides with no problem.

Yeah, they're a bit too expensive to damage on a regular basis, Allan. :-)

When I checked the Terlin site a couple of days ago, the prices didn't seem too bad.Well, not that much dearer than they were 25 years ago.

Re the tap lead, as we were mostly on 2020kHz, it usually hung off the rear vision mirror, except for occasional radphone call, or a brief call on "company" frequencies.

Often seems to be some juggling, with aerials, to get everything "right",

Bob.

As you will be using just one channel (frequency) 95% of the time (say 8022 for VKS737)- a tapped whip is more than good enough. Also, (despite what others say)..a tapped whip IS a better performr than an Autotune !!

I have used- for many years- an ole Codan 8528 with an ole Terlin multi-tap whip and have had no probs !! Yes, it has Selcall, Yes, I can (but never have used) the Telephone function. It can use 99 channels- of which I use about 5.

Cheers

just a note on terlin antenaes.

it was far cheaper for me to order one from over east delivered than is was for me to drive 10km to his shop and pick one up!!

In order to transmit at design power the antenna needs to be tuned to the frequency of the selected channel. This is not so critical on reception although theoretically it would be better if the antenna was tuned to the reception frequency, so it is unlikely that you would notice and difference in performance. Therefore, as when scanning you are only in receive mode, the radio will receive all channels scanned.

An autotune antenna automatically adjusts its tuning to the selected channel on both transmit and receive.

Incidentally, on a multi-tapped antenna there is not a tap for each and every channel. Each tap position covers a range of channel frequencies.

Well this has given me something to think about.

If understand correctly, I could have a brand new Yaesu FT857D for less than the price of a 10 year old Codan or Barrett. It would cover UHF, so I wouldn't need a stand alone UHF radio. I could build a switch to swap between my current UHF antenna and a new multi-tap HF antenna.

I would need a different licence. But that's not a reason to rule this option out.

But this setup would not be permitted by VKS737. Why do they care about what transceiver is being used? Would they know? Do other networks permit this arrangement?

Is the Yaesu FT857D as robust as the Barrett and Codans? That is, would it survive corrugations etc?

Bump - can anyone comment on this alternative?

"Bump" is an App that enables transfer of data between two smartphones. As part of the operation the phones are bumped together.

I don't see how it relates to this subject.

Hello Alan,
"bump" in this instance refers to moving ("bumping") the thread up to the top of the thread list as a consequence of the new (bump) post. Preferred method compared to starting a new thread on same subject.
Cheers Greg

These amateur radios such as the Yaesu FT857D are not type approved.
Contrary to some comments being made, type approval is not something VKS has put in place its actually the law and governs the quality and type of equipment that is allowed to be used on certain frequencies and under certain licensing conditions.

These amateur sets are not permitted to utilise the frequencies that VKS etc operate on and VKS won't grant you membership/licensing.

You will also need selcall capability to operate effectively these days.

Mobile conditions of use.

If you are only doing limited travel then hiring a sat phone is the cheapest and easiest method of communication.

Sorry Greg, I forgot to add "LOL"............lol