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koØm
05-09-2014, 02:28 PM
If you were going to purchase a 13.6 volt power supply, which one would you go for:

This one (http://www.ebay.com/itm/R-C-Power-Supply-iCharger-Hyperion-Power-Lab-iMax-Duo-Thunder-12v-575Watts-/321401014295?pt=Radio_Control_Vehicles&hash=item4ad4fe4817)

or

This one (http://www.ebay.com/itm/Pyramid-PS-26-K-Power-Supply-/261472698262?pt=US_Radio_Comm_Device_Power_Supplie s&hash=item3ce0fcbf96)

To power an Icom IC-706MKIIIG

.

K7SGJ
05-09-2014, 03:43 PM
To be honest, I'd try t find a deal on a brand name like Astron. But between the two you posted, I would take the Pyramid. I've used them before, and they are analog using pass transistors. The other, I know nothing about, and the build looks cheesy, and it is probably a switching supply. If so, and designed for RC charging, it's probably dirty as hell, and it is most likely all you will hear on the receiver. Just my ha' penny.

koØm
05-09-2014, 04:39 PM
To be honest, I'd try t find a deal on a brand name like Astron. But between the two you posted, I would take the Pyramid. I've used them before, and they are analog using pass transistors. The other, I know nothing about, and the build looks cheesy, and it is probably a switching supply. If so, and designed for RC charging, it's probably dirty as hell, and it is most likely all you will hear on the receiver. Just my ha' penny.

Basically, that's what I was thinking, the second one being a switching supply, I was concerned about noise.

.

K7SGJ
05-09-2014, 04:50 PM
Basically, that's what I was thinking, the second one being a switching supply, I was concerned about noise.

.

The one bad thing about the Pyramid, is that they push the rating to the limit. If you try to run up to rated current, the voltage sags a bit, and the current rating is not continuous duty, either. My 706mk2g pulls just under 20 amps on peaks, and the PSU is rated at 25 amps, soooooooooo, it should be okay. Not knowing how old and how much use the supply has had, you might want to throw a scope (or an AC voltmeter) and a dc voltmeter across the B+ line at full transmit to see if the B+ sags much, and if a lot of AC ripple shows up. If so, you may want to change out the caps.

KJ3N
05-09-2014, 05:33 PM
Properly designed switching supplies don't generate sufficient noise at HF. I've just about done away with all my analog supplies.

See this from August 2009 QST: http://www.centralmiarc.com/docs/Reviews/dj175t.pdf

K7SGJ
05-09-2014, 06:14 PM
Properly designed switching supplies don't generate sufficient noise at HF. I've just about done away with all my analog supplies.

See this from August 2009 QST: http://www.centralmiarc.com/docs/Reviews/dj175t.pdf

I agree that properly designed switchers have come a long way in communication applications. However, the one he has linked to is probably a wideband transmitter covering DC to light.

KC2UGV
05-10-2014, 12:30 PM
If you were going to purchase a 13.6 volt power supply, which one would you go for:

This one (http://www.ebay.com/itm/R-C-Power-Supply-iCharger-Hyperion-Power-Lab-iMax-Duo-Thunder-12v-575Watts-/321401014295?pt=Radio_Control_Vehicles&hash=item4ad4fe4817)

or

This one (http://www.ebay.com/itm/Pyramid-PS-26-K-Power-Supply-/261472698262?pt=US_Radio_Comm_Device_Power_Supplie s&hash=item3ce0fcbf96)

To power an Icom IC-706MKIIIG

.

That iCharger is just a Louisville Switcher PC power supply, that's been modded.

koØm
05-10-2014, 12:44 PM
That iCharger is just a Louisville Switcher PC power supply, that's been modded.

Wall Warts make noise but, from a completely non-scientific standpoint, I have a number of PC's and when running they haven't interfered with my radio; the real issues are 'Regulation' and risk.

Do *I* want to hook my $900.00 radio up to a $40.00 ebay "deal" or, spend money on a "Name Brand"....decision, decisions......

.

KJ3N
05-10-2014, 01:49 PM
I'm always amused at the areas were hams make "cheap" choices...

KC2UGV
05-10-2014, 02:54 PM
Wall Warts make noise but, from a completely non-scientific standpoint, I have a number of PC's and when running they haven't interfered with my radio; the real issues are 'Regulation' and risk.

Do *I* want to hook my $900.00 radio up to a $40.00 ebay "deal" or, spend money on a "Name Brand"....decision, decisions......

.

Concur. The main problem with the PC power supplies is that they supply 12V, when you really need 13.8V. And, the regulation isn't too good once you get a high current draw, so the V drops to about 10.1-9V, so your radio doesn't work right (If at all).

WØTKX
05-10-2014, 03:02 PM
Louisville Switcher sounds like "Dave Made" or something... :whistle:

K0RGR
05-11-2014, 11:32 AM
I am a fan of linear Astrons, but only from the standpoint that they are essentially bulletproof. I have one that I think has literally been turned on for 40 years, and it still works great. I picked up a second one for $100 on EBay recently, and it's powering two radios here in the home office now. But, I also have a nice little 25 amp switcher from Radio Shack that works fine most of the time. I have observed situations where it generated RF noise like there was no tomorrow, and I'm not sure why it would be different, but it's completely quiet in my radio shack.

Switchers have one plus, which is that they tend to fail in a way that kills the voltage output - the linear supplies can fail with too much voltage on their output! The biggest issue with the Radio Shack supply is the noisy fan in it. I use the RS supply for any kind of portable work.

n0iu
05-11-2014, 11:59 AM
I'm always amused at the areas were hams make "cheap" choices...

I always get a kick out of the emcomm whackers who are looking for the cheapest this or the cheapest that for their "go box". I mean here they are wanting to cobble together a communications system that could potentially be used to save lives, but yet the are always looking for the cheapest doohickey instead of the best thingamajig to do the job.

K7SGJ
05-11-2014, 12:48 PM
I am a fan of linear Astrons, but only from the standpoint that they are essentially bulletproof. I have one that I think has literally been turned on for 40 years, and it still works great. I picked up a second one for $100 on EBay recently, and it's powering two radios here in the home office now. But, I also have a nice little 25 amp switcher from Radio Shack that works fine most of the time. I have observed situations where it generated RF noise like there was no tomorrow, and I'm not sure why it would be different, but it's completely quiet in my radio shack.

Switchers have one plus, which is that they tend to fail in a way that kills the voltage output - the linear supplies can fail with too much voltage on their output! The biggest issue with the Radio Shack supply is the noisy fan in it. I use the RS supply for any kind of portable work.

This is why, even with crowbar circuits inside, I still fuse, and put a suitable wattage zener across the output of the PSU. A 15 volt zener, and an appropriate SB fuse work great for my communications applications. Most radios can tolerate that much of a temporary overvoltage without damage.

K0RGR
05-12-2014, 02:46 PM
This is why, even with crowbar circuits inside, I still fuse, and put a suitable wattage zener across the output of the PSU. A 15 volt zener, and an appropriate SB fuse work great for my communications applications. Most radios can tolerate that much of a temporary overvoltage without damage.

Yes, good plan. I have an external overvoltage warning on my big Astron, which I check before I turn on the rigs, but the zener is probably a better idea.

W3WN
05-14-2014, 07:09 AM
If you were going to purchase a 13.6 volt power supply, which one would you go for:

This one (http://www.ebay.com/itm/R-C-Power-Supply-iCharger-Hyperion-Power-Lab-iMax-Duo-Thunder-12v-575Watts-/321401014295?pt=Radio_Control_Vehicles&hash=item4ad4fe4817)

or

This one (http://www.ebay.com/itm/Pyramid-PS-26-K-Power-Supply-/261472698262?pt=US_Radio_Comm_Device_Power_Supplie s&hash=item3ce0fcbf96)

To power an Icom IC-706MKIIIG

.To be perfectly honest... neither.

I'd be looking for one of these: http://www.ebay.com/itm/astron-rs-20a-/111348623470?pt=US_Radio_Comm_Device_Power_Supplie s&hash=item19ece5286e
Or one of these: http://www.ebay.com/itm/Astron-RS-35A-Power-Supple-Ham-Radio-/151291032046?pt=US_Radio_Comm_Device_Power_Supplie s&hash=item2339a5f1ee

The RS-20 should be MORE than adequate to run a 100 W transceiver. I used one for many, many years, feeding a TS-430S or a TS-440S or a TS-480SAT at various times. Rarely did the rig ever "demand" more current than the Astron could supply... come to think of it, I can't think of a single time the Astron failed me until something blew in the regulator board.

I ended up giving the remants of that PS away. Simply because I bought a used RS-35A at a hamfest for less than what Astron wanted for a new board.

W3WN
05-14-2014, 07:14 AM
Wall Warts make noise but, from a completely non-scientific standpoint, I have a number of PC's and when running they haven't interfered with my radio; the real issues are 'Regulation' and risk.

Do *I* want to hook my $900.00 radio up to a $40.00 ebay "deal" or, spend money on a "Name Brand"....decision, decisions......

.So buy a new Astron. R & L will sell you one for $112.95 (plus tax/S&H) See http://www.randl.com/shop/catalog/product_info.php?products_id=29398 . Or shop around, you can find better prices out there if you look around.

The Astron supply is simply, straight forward, long lasting (the one I had that blew had been in continuous duty -- and I mean all the time "on" -- for over 20 years. And I got it used from W3SRL, who bought it new and had it for a few years) and rugged. It's worth the price.

koØm
05-14-2014, 06:33 PM
So buy a new Astron. R & L will sell you one for $112.95 (plus tax/S&H) See http://www.randl.com/shop/catalog/product_info.php?products_id=29398 . Or shop around, you can find better prices out there if you look around.

The Astron supply is simply, straight forward, long lasting (the one I had that blew had been in continuous duty -- and I mean all the time "on" -- for over 20 years. And I got it used from W3SRL, who bought it new and had it for a few years) and rugged. It's worth the price.

Thanks for the heads-up, I searched around and found this one

http://www.ebay.com/itm/191163894181?ssPageName=STRK:MEBOFFX:IT&_trksid=p3984.m1432.l2649

and made him an offer on it at less than the Buy-It-Now price; there are ten of them available.

If all else fails, I will go and see Rita and Larry up in Hamilton.

.

ETA: Rita was a fine looking woman in her day, haven't seen her in the store in quite a while.

koØm
05-19-2014, 07:29 AM
UPS shipping notice says that it will be delivered tomorrow.

I saw some marvelous looking switching supplies in the main arena but the crush of humanity HAM-anity made it hard to get detailed info. Fortunately I have catalogues from all the major vendors who were there so I have plenty of reading material as well as "necessity paper" for the out-house.

.

N2ADV
05-20-2014, 08:46 AM
I ended up giving the remants of that PS away. Simply because I bought a used RS-35A at a hamfest for less than what Astron wanted for a new board.
I went through 2 RS-35A's in the past couple years. Both went "bzzzzzzzzzt!" (Literally) and went Tango Uniform and I haven't had time to tear them a apart and figure out wtf happened. Both blow fuses now right away.

I have a cheap JetStream switcher (JTPS31MB) that is quiet as hell and chugs along nicely.