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

donate to eham
   Home   Help Search  
Pages: Prev 1 2 [3] 4 5 Next   Go Down
  Print  
Author Topic: Is Astron still king?  (Read 2294 times)
G3RZP
Member

Posts: 1221




Ignore
« Reply #30 on: July 18, 2019, 04:47:41 PM »

So what you guys are appearing to be saying is that MTTR is important, and the Astron (or I guess, any other good linear supply) is likely to have a much lower MTTR than any switcher. that goes along with my feeling - experience has shown that when a switcher fails, there has normally been a chain reaction taking out more than  a few semiconductors. OF course being an 'old fart', I'm much happier with analogue circuitry than switchers...
Logged
WA7ARK
Member

Posts: 609




Ignore
« Reply #31 on: July 18, 2019, 05:49:43 PM »

MTTR?
Logged

Mike, WA7ARK
K0UA
Member

Posts: 4330




Ignore
« Reply #32 on: July 18, 2019, 05:55:42 PM »

The first picture is with one of the lamps replaced with LED's.  (only one was burned out) this shows the difference between the old incandescent lamp and the LED

 And second pix is with both replaced.



Logged

73  James K0UA
ARRL Missouri Technical Specialist
K0UA
Member

Posts: 4330




Ignore
« Reply #33 on: July 18, 2019, 05:57:17 PM »

MTTR?

Mean Time To Repair.  Or we might say Mean Time Between Failure.
Logged

73  James K0UA
ARRL Missouri Technical Specialist
W9IQ
Member

Posts: 3212




Ignore
« Reply #34 on: July 19, 2019, 03:35:39 AM »

MTTR is the initialism for mean time to repair. It is the average time it takes to repair something once it has failed or broken.

MTBF is the is the initialism for mean time between failures. This is the average "run" time before a device fails.

The general engineering goal is therefore to maximize MTBF and minimize MTTR as this will result in the greatest availability of the equipment. There are many variations to this goal, however. For example, if the acquisition cost of the equipment is low and the MTBF is high, then the MTTR may not matter - it is considered throw away since the total cost of repair may exceed the replacement cost.

- Glenn W9IQ

« Last Edit: July 19, 2019, 03:48:13 AM by W9IQ » Logged

- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
WB5UAA
Member

Posts: 96




Ignore
« Reply #35 on: July 19, 2019, 05:21:31 AM »

MTTR is the initialism for mean time to repair. It is the average time it takes to repair something once it has failed or broken.

MTBF is the is the initialism for mean time between failures. This is the average "run" time before a device fails.

The general engineering goal is therefore to maximize MTBF and minimize MTTR as this will result in the greatest availability of the equipment. There are many variations to this goal, however. For example, if the acquisition cost of the equipment is low and the MTBF is high, then the MTTR may not matter - it is considered throw away since the total cost of repair may exceed the replacement cost.

- Glenn W9IQ



EXACTLY!

I was a fan of Astron for many years.  Big, heavy, silent, solid, reliable power supplies.  Then one day, that little red rocker on/off switch fell apart.  After some significant googling, I found a replacement.  When I saw the price for another little red rocker switch, I decided it's time to upgrade my power supplies to the more modern "disposable" power supplies of today.  (After all, that's where we are in the "state" of electronics today.)  I practically gave away my three Astrons (couple of 35s and a 20.)  Now I have a *supply* of some MFJ switchers (~$100 each, two NIB on my shelf) and I don't see any noise on the HF radio.  I also have some Alinco switchers with a knob on the front that varies the switching frequency (I've never adjusted them...) if you need to move the noise on the HF radio.  I like the small, lightweight power supplies now.  And they take up much less space in the operating position.  And if anything goes wrong, I take the whole power supply, throw it in my recycle box and replace it with a brand new power supply.  No more trying to *fix* an old, dusty, aging, "going to break again soon," heavy, takes up a lot of space, hard to find parts for power supply.

I was an electronics maintenance guy for many years.  We're becoming obsolete.  (If not already obsolete...)

But then again, to each is own!
Logged
KC0MYW
Member

Posts: 88




Ignore
« Reply #36 on: July 19, 2019, 07:51:31 AM »


When I saw the price for another little red rocker switch, I decided it's time to upgrade my power supplies to the more modern "disposable" power supplies of today.


Not sure what you were able to find, and of course prices and availability of things change over time so that could play a part.

I recently acquired another linear Astron supply (It's a RS-12A and I intend to use it for other-than-radio purposes) and in searching for some new rubber feet for it I was doing some online research to try and find a part number. I ended up getting https://www.mouser.com/ProductDetail/3M-Electronic-Specialty/SJ-5023-BLACK?qs=sGAEpiMZZMs6x5FGDTpfsAVq%252BWJOTwqsfembSiiSRXE%3D and they appear to be correct, but I have not put them on yet.

One of the pages I happened across in my research was: http://www.repeater-builder.com/astron/astron-repair/astron-repair.html
On that page, there is some information regarding some "commonly replaced parts" and a part number for a new rocker switch.

I don't have a need for a new rocker switch at this time, but as I was ordering anyway and that switch is here:
https://www.mouser.com/ProductDetail/Carling-Technologies/LRA211-RS-B-125N?qs=sGAEpiMZZMsqIr59i2oRcjvnT%252BmcDpesWNFWAnxYOSs%3D
I decided to get a couple to have on hand in case I ever do need one, they are only $1.01 each at the current time.

Now, I do also have a couple of switching supplies (not Astrons) and they are definitely smaller, lighter, and (I haven't personally measured) supposed to be more energy efficient. I like both linear and switching supplies for different reasons and different purposes, it all depends on the goals and requirements.
Logged
VA3VF
Member

Posts: 2860




Ignore
« Reply #37 on: July 19, 2019, 08:05:54 AM »

Quote
I was an electronics maintenance guy for many years.  We're becoming obsolete.  (If not already obsolete...)
I was in the consumer electronics business in the late 80's early 90's. In the early 90's, a decision was made that equipment up to a certain $ value would simply be replaced with a new one, no servicing. A bunch of technicians were let go as a result.

Then, early in the 21st century, at another place, all the electronics guys became computer guys. The justification: everything is a computer these days.
« Last Edit: July 19, 2019, 08:23:32 AM by VA3VF » Logged
W9WD
Member

Posts: 123


WWW

Ignore
« Reply #38 on: July 19, 2019, 08:10:19 AM »

I think I should have asked if Astron is still "King of the linear amps".

I like the idea of brute force in power supplies.
Simple and powerful.
Logged

Greg
On the continental divide in the wilds of New Mexico.
W9IQ
Member

Posts: 3212




Ignore
« Reply #39 on: July 19, 2019, 08:11:32 AM »

What often drives these decisions is the cost of labor for the repair. The parts costs are typically quite low.

So as hobbyists, we can often ignore the labor cost or even justify it for the sake of learning or self satisfaction. This another reason for the popularity of the Astron line - they are easy to service and it is trivial to find the appropriate parts.

- Glenn W9IQ
Logged

- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
W1VT
Member

Posts: 3292




Ignore
« Reply #40 on: July 19, 2019, 08:35:24 AM »

The hardest part of building your own high power linear power supply is finding the high current transformer.
Logged
N9AOP
Member

Posts: 1149




Ignore
« Reply #41 on: July 19, 2019, 09:50:09 AM »

The Astron 'brick' supplies are nice for the home station and seem to last forever but for portable use I like the Samlex.
Does anyone remember the 100amp 12V supply made by TenTec?  It was about the size of a college dorm room refrigerator and you needed a fork lift to move it.
Art
Logged
W5DXP
Member

Posts: 4656


WWW

Ignore
« Reply #42 on: July 19, 2019, 11:52:13 AM »

There is probably a power output value where the switching power supply wins overall. To me it seems to be around 500 watts.
Logged

My antenna says, "What makes me happy is when the tuner is adjusted for maximum available current through my radiation resistance!" 73, Cecil, w5dxp.com
W9IQ
Member

Posts: 3212




Ignore
« Reply #43 on: July 19, 2019, 12:17:30 PM »

There is probably a power output value where the switching power supply wins overall. To me it seems to be around 500 watts.

I think that is a good observation, Cecil.

- Glenn W9IQ
Logged

- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
W9IQ
Member

Posts: 3212




Ignore
« Reply #44 on: July 19, 2019, 01:14:41 PM »



- Glenn W9IQ
Logged

- Glenn W9IQ

I never make a mistake. I thought I did once but I was wrong.
Pages: Prev 1 2 [3] 4 5 Next   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!