Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-08 Thread paul swed
Charles is absolutely correct this is what I have seen in these large splitters. I have a really nice one that you can take the cover off and look. Lots of screws. Regards Paul WB8TSL On Thu, Jan 8, 2015 at 5:03 AM, Charles Steinmetz wrote: > Dave wrote: > > Yes, but I was aware of this, and th

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-08 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
On 8 January 2015 at 10:03, Charles Steinmetz wrote: > Dave wrote: > >> Yes, but I was aware of this, and that's why I got two different isolation >> figures. > > > What I was pointing out is that there will be *4* different isolation > figures from any one output port, not just two. The lowest w

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-08 Thread Charles Steinmetz
Dave wrote: Yes, but I was aware of this, and that's why I got two different isolation figures. What I was pointing out is that there will be *4* different isolation figures from any one output port, not just two. The lowest will be to the one electrically adjacent output, next (a bit highe

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-08 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
On 7 Jan 2015 01:24, "Charles Steinmetz" wrote: > > Dave wrote: > >> At 50 MHz, the loss from the common port is 12.8 dB, and the isolation >> between two ports sets of ports is either 38 or 48 dB > > > To get the worst-case output-to-output isolation, you need to test two output ports that are el

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-06 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
Just to say, the comment on the graphs that the VNA covers 50 MHz to 20 MHz, is obviously wrong. My 8720D covers 50 MHz to 20 GHz. I do have another couple of VNAs here that cover 10 MHz. I will do some more measurements, with a more suitable VNA when I have both splitters here and some time for

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-06 Thread Charles Steinmetz
Dave wrote: At 50 MHz, the loss from the common port is 12.8 dB, and the isolation between two ports sets of ports is either 38 or 48 dB To get the worst-case output-to-output isolation, you need to test two output ports that are electrically adjacent (i.e., that share the same last 2:1 spli

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-06 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
On 4 January 2015 at 02:37, Bob Camp wrote: > Hi > >> On Jan 3, 2015, at 6:09 PM, Dr. David Kirkby (Kirkby Microwave Ltd) >> wrote: >> >> I was looking to make a 10 MHz distribution amp to feed test equipment with >> the output of a GPSDO. >> >> I see this >> >> http://m.ebay.com/itm/20124430235

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-06 Thread Magnus Danielson
ate: Sun, 4 Jan 2015 08:29:34 -0500 Subject: Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier? A cheap and dirty equivalent of a pass thru terminator that I use is a BNC t connector with a 52 ohm bnc terminator. I guess you could use a CATV 75 oh

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-06 Thread Tom Knox
> To: time-nuts@febo.com > Subject: Re: [time-nuts] Any reason not to use one power amplifier and > splitter for distribution amplifier? > > Hi > > Any time you run into terms like “low noise” it pays to think about what that > means to you and your system. A qui

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-05 Thread Bob Camp
> > >> From: bill.ric...@verizon.net >> To: time-nuts@febo.com >> Date: Sun, 4 Jan 2015 08:29:34 -0500 >> Subject: Re: [time-nuts] Any reason not to use one power amplifier and >> splitter for distribution amplifier? >> >> A cheap and dirty

[time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?...

2015-01-05 Thread Burt I. Weiner
of very good products out there on the surplus market selling for a small fraction of their original cost. Cheers; Thomas Knox > From: bill.ric...@verizon.net > To: time-nuts@febo.com > Date: Sun, 4 Jan 2015 08:29:34 -0500 > Subject: Re: [time-nuts] Any reason not to use one power

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-05 Thread Tom Knox
original cost. Cheers; Thomas Knox > From: bill.ric...@verizon.net > To: time-nuts@febo.com > Date: Sun, 4 Jan 2015 08:29:34 -0500 > Subject: Re: [time-nuts] Any reason not to use one power amplifier and > splitter for distribution amplifier? > > A cheap and dirty

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-05 Thread billriches
A cheap and dirty equivalent of a pass thru terminator that I use is a BNC t connector with a 52 ohm bnc terminator. I guess you could use a CATV 75 ohm F type with an adapter. Maybe that combination would produce too much garbage. 73, Bill, WA2DVU Cape May --- This email has been checked for

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-05 Thread Charles Steinmetz
Bruce wrote: A 10nF cap connected to the emitter winding [instead of the collector] avoids capacitively coupling collector power supply noise to the output (assuming that the collector supply isnt ground.). Good point. I take pains with power supply design and very rarely have problems with

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-04 Thread Bob Camp
Hi > On Jan 3, 2015, at 10:37 PM, paul swed wrote: > > Dave > I am sure there will be many answers. But yes indeed it will work fine. All > of the outputs should have the same delay also and that may be useful. > > There really are the two approaches. The big power amp thats a 1/2 Watt you > ar

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-04 Thread Bruce Griffiths
On Sunday, January 04, 2015 03:39:48 AM Charles Steinmetz wrote: > Dave wrote: > >I was looking to make a 10 MHz distribution amp to feed test equipment with > >the output of a GPSDO. > > > > * * * > > > >16-way Minicircuits splitter on eBay which I got for $40. I guess the loss > >is aro

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-04 Thread Charles Steinmetz
Dave wrote: I was looking to make a 10 MHz distribution amp to feed test equipment with the output of a GPSDO. * * * 16-way Minicircuits splitter on eBay which I got for $40. I guess the loss is around 12 dB. Is there any reason not to just drive that with 22 dBm or so of power to get

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-04 Thread Bruce Griffiths
Almost all frequency counters have an internal source which is a potential means of injection locking an external reference if the isolation between the internal source and the external source is inadequate. High impedance taps on a single terminated line ensure that the isolation between such i

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-04 Thread Bill Hawkins
Friends in Time, There's been a large amount of discussion about distribution amps on this list. People may be using them just because that's what's done. So I ask you: What are we trying to isolate? The destination devices do not generate an interfering signal, n'est ce pas? The receiving devic

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-03 Thread Joseph Gray
My 2 cents. I just repurposed an RGB video distribution amp for use with a rubidium. The board has three EL2070 (200 MHz BW) amps, each one feeds several BNC jacks for RGB output. I only need three separate, isolated outputs, so I am feeding the rubidium into all three EL2070's and only taking one

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-03 Thread paul swed
Dave I am sure there will be many answers. But yes indeed it will work fine. All of the outputs should have the same delay also and that may be useful. There really are the two approaches. The big power amp thats a 1/2 Watt you are talking and the many small amps as in the distributed mode. Whats

Re: [time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-03 Thread Bob Camp
Hi > On Jan 3, 2015, at 6:09 PM, Dr. David Kirkby (Kirkby Microwave Ltd) > wrote: > > I was looking to make a 10 MHz distribution amp to feed test equipment with > the output of a GPSDO. > > I see this > > http://m.ebay.com/itm/201244302355 > > 16-way Minicircuits splitter on eBay which I go

[time-nuts] Any reason not to use one power amplifier and splitter for distribution amplifier?

2015-01-03 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
I was looking to make a 10 MHz distribution amp to feed test equipment with the output of a GPSDO. I see this http://m.ebay.com/itm/201244302355 16-way Minicircuits splitter on eBay which I got for $40. I guess the loss is around 12 dB. I actually bought another for $35 which was similar but o