Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Mark A. Holman
If I did that my XYL would string me by a wall wart ! :) shes tolerable to my hobby and I have to put up with cats ! - Original Message - From: "Dave VanHorn" <[EMAIL PROTECTED]> To: Sent: Tuesday, July 19, 2005 5:03 PM Subject: Re: [Repeater-Builder] IOTA Switched

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Dave VanHorn
At 05:18 PM 7/19/2005, Tony King, W4ZT wrote: >One caution about these switchers. Many of the cheap switchers being >made today both as chargers and supplies generate tremendous amounts of >RFI. A number of my ham friends have experienced unbearable >interference from these devices. Note that the

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Tony King, W4ZT
One caution about these switchers. Many of the cheap switchers being made today both as chargers and supplies generate tremendous amounts of RFI. A number of my ham friends have experienced unbearable interference from these devices. Note that they have no part 15 certification and you can ne

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Joe Montierth
--- Mike Morris WA6ILQ <[EMAIL PROTECTED]> wrote: > I did this at a friend house and we ended up with > about 20 > plugged into a half-dozen power strips and totalling > about > 2 and a half amps of AC... He's got 112-114v of AC > at his > house so using 113 we get 255.2w ... divide by 1000 > a

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Dave VanHorn
> >Think how many houses have that exact same situation. I know I suffer from this big-time. Lots of wall wart devices. They are going to switchers though, it's finally come to the place where the switcher is cheaper than the iron and shipping from China. Last year, I needed a new wart for somet

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Mike Morris WA6ILQ
One nit-pick: measure the actual AC line voltage and use it where Joe has "115v". Locally it's 118-123v, depending on the local load (i.e. lower on a summer day, highest during a winter night). And sometime when you have a free hour, wander around the house and count how many wall warts you have

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Joe Montierth
The easiest way to tell would be to measure the AC current draw in idle. Then measure the DC current draw in idle. You can get a pretty close watt figure by multiplying the amps times the voltage (115v) on the input side, and doing the same thing on the DC side. The difference between the two is y

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Dexter McIntyre W4DEX
Anyone have an idea how much power would be saved by running a MSF-5000 that is idle most of the time from a switcher instead of the stock heavy iron power supply?. The transformers produce a lot of heat just in standby mode. I have several of these machines on line and also a GE repeater wit

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Dave VanHorn
> >If you do the calculations on wasted heat, this comes >to an additional 4147 KWh per year on the Astron, and >an additional 1175 KWh/ year on the IOTA. If you live >in an area with 10 cents/KHh power (typical) then your >power savings in one year will be almost $300. We don't pay the power bil

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Joe Montierth
Dave's points are good, I'd like to point out a couple of other things. We have used Astron supplies for years, and overall have been happy with them. There are some drawbacks, mainly the analog design is very wasteful of power, and the units get very warm (hot). I have done some measurements, and

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Dave VanHorn
At 09:43 AM 7/19/2005, Gran Clark wrote: >Joe > >Carefully consider expanding into switchers. The designs are quite >varied. To repair them you really need a good high frequency scope, >shielded isolation transformer, 0.18 ohm 1000 watt resistor load, >and most of all a good schematic. Switc

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-19 Thread Gran Clark
to replace my power supplies in the future.  Bruce KD4BOH.-  Original Message - From: "Joe Montierth" <[EMAIL PROTECTED]> To: Sent: Wednesday, May 25, 2005 2:22 PM Subject: Re: [Repeater-Builder] IOTA Switched Power Supply and Noise? >I have one of the 75 amp supplies

RE: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-17 Thread Richard
2005 4:49 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] IOTA Switched Power Supply and Noise? Does anybody have a web site to look at IOTA power supply? I need to find some to replace my power supplies in the future. Bruce KD4BOH.- Original Message - From: &quo

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-17 Thread Dave VanHorn
At 06:49 PM 7/17/2005, Bruce Nanney wrote: >Does anybody have a web site to look at IOTA power supply? I need to find >some to replace my power supplies in the future. Bruce KD4BOH.- I picked up one on ebay recently, very competitive pricing. Yahoo! Groups Links <*> To visit your grou

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-07-17 Thread Bruce Nanney
er-Builder] IOTA Switched Power Supply and Noise? >I have one of the 75 amp supplies working at a remote > site. We have not seen any noise from the unit, but > our equipment is all VHF and UHF, haven't checked it > down in HF, but at UHF we have seen no problems. We > have 20 UHF

Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-05-25 Thread Joe Montierth
I have one of the 75 amp supplies working at a remote site. We have not seen any noise from the unit, but our equipment is all VHF and UHF, haven't checked it down in HF, but at UHF we have seen no problems. We have 20 UHF RX's and 6 VHF and have not seen any degradation. These IOTA's run much coo

[Repeater-Builder] IOTA Switched Power Supply and Noise?

2005-05-25 Thread Nick Papadonis
Hi Folks, I'm considering purchasing a 45A IOTA Switched Power supply to power a UHF Micor and am concerned about switch PS noise. Has anyone tried these supplies with UHF radios? Is noise experienced? Insight greatly appreciated. Thanks. -- Nick KB1GZN Boston, MA Yahoo! Groups Links