Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: Realistically priced mobile HF amps...  (Read 8026 times)
KT0DD
Member

Posts: 278




Ignore
« on: July 12, 2012, 04:31:16 AM »

Hello, I am submitting this for suggestion only. I know type accepted amplifier laws and would never jeapordize my license or wish to pollute the bands with an illegal CB amp.

There seems to be a void in the mobile amp market. Ameritron ALS 500m seeems to be the only offering in the mobile market right now. The Tokyo Hy-Power, SGC 500 Cube etc. are either discontinued or ridiculously priced.

Just for price comparisons, I emailed a CB amp trader and asked about costs. His offering was a unit (yes - a dirty illegal one) with 4 2SC2879 transistors for $ 389. Ameritrons amp is $ 800 +.

Surely a mobile amp can be designed type accepted for less than  $800.  Does adequate filtering and design really add $ 400 more to the cost of an amp?  Maybe if someone could design a clean amp for $ 500-600. there would be less incentive for people to resort to buying dirty CB amps.

Just an Idea.   73.   Todd - KT0DD
Logged
NA4IT
Member

Posts: 885


WWW

Ignore
« Reply #1 on: July 12, 2012, 04:39:29 AM »

When you start looking at the different bands an amateur amp has to cover, there is a much more advanced circuit design there, consisting of input and output filters, band switching, etc.
Logged
KG4NEL
Member

Posts: 373




Ignore
« Reply #2 on: July 12, 2012, 06:32:03 AM »

When you start looking at the different bands an amateur amp has to cover, there is a much more advanced circuit design there, consisting of input and output filters, band switching, etc.

Mobile amps seem like the perfect candidate for a much more reasonably-priced single band design. A limitation of a single or a few bands might not be as much of a hindrance mobile, where QSYing can be more "involved" than at home.
Logged
N3JBH
Member

Posts: 2358




Ignore
« Reply #3 on: July 12, 2012, 06:35:50 AM »

I believe part of the  problem with Amateur amp design for commercial production is the recouping of the cost of all the testing and certification cost involved in bring them to market as well. So it may just be a case of passing along them cost as well as the cost of material's you physically see in the amp itself.
Logged
W9GB
Member

Posts: 2626




Ignore
« Reply #4 on: July 12, 2012, 07:26:53 AM »

Quote from: KT0DD
There seems to be a void in the mobile amplifier market.
Ameritron ALS 500m seeems to be the only offering in the mobile market right now.

Not a void -- just the reality of the radio amateur consumer market.
Amateur radio has never been a "cheap" hobby or consumer/appliance oriented,
BUT the capabilities and skills for DIY by the new amateur are far less than 40 years ago.


Quote from: KT0DD
The Tokyo Hy-Power, SGC 500 Cube etc. are either discontinued or ridiculously priced.
ECONOMICS.
The March 2011 earthquake and tsunami ... was a terrible loss of life and the resulting Fukushima nuclear disaster crippled Japan's electrical power generation.
This forced relocation of Japanese companies and residents in the Fukushima Prefecture as a result of a radioactive zone.

You may have noticed Yaesu prices on antenna rotators almost doubling in price since March 2011 ...
some of their production facilties and sub-contractors were in the Fukushima Prefecture
http://en.wikipedia.org/wiki/Fukushima_Prefecture
Yaesu operations and production had to be moved to other areas in Eastern Asia (Japan, Singapore, Malaysia, China).

In addition, since the 2008 Global Financial Crisis, the major global currencies (except Swiss Franc) have dropped versus Japanese Yen.

Quote from: KT0DD
Just for price comparisons, I emailed a CB amp trader and asked about costs.
His offering was a unit (yes - a dirty illegal one) with 4 2SC2879 transistors for $ 389. Ameritrons amp is $ 800 +.
APPLES and ORANGES.
Common comment from new radio amateurs and former CB operators .... for past decade ...
comparing a cheap car with NO transmission (one gear/speed) to a Chevy with a 5-speed transmission.

CB amplifiers are designed for ONE band (27 MHz).. to further reduce costs then they omit the Output Flitering that removes
the undesirable (dirty) harmonics of the primary (desired) frequency.  Many are a Heat sink, case and the RF transistors on a PCB.
You would NEVER build an automobile like this ... but that does not stop Texas Star, Dave Made, RM Italy, etc. selling at a price point.
Marketed like diet pills with meaningless slang terms to an anti-science/anti-technology audience: Swing, MoPower

The COST for amateur radio mobile HF amplifiers ($$) is largely associated with cleaning up the IMD of 12 VDC RF devices and
building the 6 to 8 band filtering (and its switching -- manual or electronic/manual) for reqeusted freqency agility and flexibility (market demand).

The RF power transistor manufacturers (Japan, US, Europe) have moved to 24/28 V (aviation/military); 50 V (telecom/broadcast)
and ~100V solid-state devices.  The days of the 12 V RF Power device peaked in 1980s, and have a limited market today.
Little new development is being performed at the 12 DC power input level for HF frequencies.

Quote from: KT0DD
Surely a mobile amplifier can be designed type accepted for less than $800.  
Does adequate filtering and design really add $ 400 more to the cost of an amp?  
Maybe if someone could design a clean amp for $ 500-600. there would be less incentive for people to resort to buying dirty CB amps.
SHOW ME THE MONEY.
YES, IF the Mobile Amplifier was for one amateur band .... it solution is easier ....
but the product has a limited usefulness (daily/seasonal/solar cycle band changes) when the chosen HF band is not useful for communications.

Additionally, even if you built an single band amplifier for the longer wavelength bands (80,40, 20) .....
the antenna has to be electrically longer .. which is a challenge (adding cost) for mobile operations.


The COST is due to the consumer's (radio amateur) desire to operate everywhere on HF ... that Flexibility and Agility (QSY) has a price.
Except for the US military ... those requirements do not exist for any other commercial customer.
Your local AM/FM/TV broadcast owner/operator can optimze their station/operations (transmitter, antennas, towers) since they are on ONE frequency.

Like Gravity, Radio/RF (Electromagnetic Waves) follows the Laws of Physics.
You can not be in denial of Nature's "Rules of the Game"

===
w9gb
« Last Edit: July 12, 2012, 07:47:46 AM by W9GB » Logged
WB2WIK
Member

Posts: 20611




Ignore
« Reply #5 on: July 12, 2012, 10:52:31 AM »

I'd sink the money into a better mobile antenna system, more bang for the buck.

100W into a very large-scale screwdriver antenna mounted up high on the vehicle with a welded bracket and a great grounding system is better than 500W into a smaller whip every time.  10dB+ for the antenna vs. 7dB for the amp. Wink

Some mobile rigs like the TS-480HX run 200W, so then a 500W amp is only a 4dB improvement: Hardly worth it, even if the amp was nearly free.

Logged
KC9TNH
Member

Posts: 304




Ignore
« Reply #6 on: July 15, 2012, 05:34:34 AM »

I'd sink the money into a better mobile antenna system, more bang for the buck.

100W into a very large-scale screwdriver antenna mounted up high on the vehicle with a welded bracket and a great grounding system is better than 500W into a smaller whip every time.  10dB+ for the antenna vs. 7dB for the amp. Wink

Some mobile rigs like the TS-480HX run 200W, so then a 500W amp is only a 4dB improvement: Hardly worth it, even if the amp was nearly free.


Pretty good economic analysis above & then Steve's post is like the easy-button. I've noticed when picking up a mobile on one net or other (75/40/20, all over the country) that the really good signals may only be running 50-100w on a pretty generic radio. Invariably, though, when describing their setup (time permitting) there is alot of detail focused on their antenna (and grounding grounding grounding). An amp is the afterthought, i.e., "yeah, someday I'd like to get..." But it's antenna antenna antenna.
Logged

73
Wes -KC9TNH
"Don't get treed by a chihuahua." - Pete
WD5GWY
Member

Posts: 403




Ignore
« Reply #7 on: July 15, 2012, 10:40:26 AM »

In mobile HF it is definitely "all about the antenna". That includes good installation.
I have used hamstick antennas, a 102" whip and LDG autotuner and now a Tarheel
100a HP. The difference between the three, especially on the low bands is very noticeable.
I run an ICOM 706 MKIIG and no amp. Get good to great signal reports on 80-10 meters.
A lot of time and work went into installing the antenna on my Dodge Pickup and getting
proper bonding between all the different components. (cab, bed, frame and even the exhaust) I had done some of that work before the screwdriver antenna, while the other
methods worked, once I got serious about the antenna and bonding, I ended up with a
setup that works very well for me. At 100 watts, I don't feel the need for an amp. Although I will say I have been tempted by the ALS-500. But, when someone on 40 meters says I'm
20 over with 100 watts (and at that point the best screwdriver antenna starts loosing efficiency) then adding the extra 400 watts seems pointless. I also have a Kenwood TS-480SAT in my 18 wheeler that I drive at work. (using a Little Tarheel II) Given the shortened size of the Little Tarheel, it might have been better to get the HX version for the little extra punch and the the lack of performance of the smaller antenna compared to the larger (and more difficult to safely install on an 18 wheeler) Tarheel antennas.
That extra 100 watts "might" make a difference. But, if I had a good spot on the truck to install a larger antenna, I'd go with that instead. Mobile Amps are nice, but, they add to the complexity of the installation. Which may or may not be worth the effort.
  There just really is no way as has been mentioned to make a CLEAN amp for less than the ALS-500. And you can find them used for as little as $500 give or take a bit. So, to me that is a good alternative. Mobile amps are just not a big enough market for manufacturers to mass produce them at the price point you are interested in without compromising quality.
james
WD5GWY
     
Logged
WX7G
Member

Posts: 6131




Ignore
« Reply #8 on: July 15, 2012, 01:43:12 PM »

I worked mobile CW for awhile using an ALS-500 and found it to be more trouble than it was worth. I ended up selling the amp and going with an autotuning screwdriver antenna at 100 watts. I don't miss the amp and my frequent band changes are quick and easy.
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!