Re: [time-nuts] Minicircuits specs
Gerhard Hoffmann wrote: Am 29.11.2014 um 20:01 schrieb Gerhard Hoffmann: Am 29.11.2014 um 19:08 schrieb Thomas S. Knutsen: 2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Ok, I volunteer to measure the S21 of a dc-force-fed T1-1 or T4-1 next weekend, when I'm back home. (DG8SAQ VNWA and / or WG TSA-2) Really, on osc, a voltmeter and a DC source are enough. Here it is: Mini circuits T1-1T, new very old stock, still in black case, not one of the new whitish ones that turn brown in the week after soldering. 0 / 25 / 50 / 100 mA on the secondary side from Agilent 6633B dc supply. It is nice that you can directly type in the voltages or currents. But you better do not take this thing for anything that is sensitive to noise. DG8SAQ VNWA, my best DC block from PSPL because it also has the lowest lower corner. It took some experimenting to find a choke that would not modify S21 and carry the current. Finally: a medium size red Amidon core two 220uH Siemens chokes with a looong air gap. https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The low frequency corner suffers already at 25 mA. The high frequency side is unimpressed by the current. Just what one expects from a transmission line transformer that gets ferrite as an anabolicum for the low frequencies. The transformer survived 1A for a short time and did not seem to suffer from that abuse s-parameter-wise. regards, Gerhard Many thanks for the graphs, Gerhard. I suspected that the low end would be the first to suffer, but didn't know how much. Those curves explain the reason for the 30ma limit; it's to keep the devices' specs definable. With a higher limit, the insertion loss specs would be terrible, and nobody would buy them. The text on the screen shots is a bit hard to read, but I think the curves told me what I wanted to know..As with most other devices, it's best to stay away from the Max figures on the datasheet. Thanks for taking the trouble to make the measurements and share the results. Dave M ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Please Gerhard, more details on your choke (medium size red Amidon core two 220 uH Siemens chokes). Maybe I can use it for 160 meter antennas. Your T1-1 measurements make sense according to my experience with these things. The -6 series (T1-6, etc) has larger cores and should withstand more DC. (I like to take apart MCL stuff to see what is inside; very enlightening). I always use the -6 series for 160 meter work. Thanks, 73 Rick Karlquist N6RK On 12/7/2014 10:14 PM, Gerhard Hoffmann wrote: Am 29.11.2014 um 20:01 schrieb Gerhard Hoffmann: DG8SAQ VNWA, my best DC block from PSPL because it also has the lowest lower corner. It took some experimenting to find a choke that would not modify S21 and carry the current. Finally: a medium size red Amidon core two 220uH Siemens chokes with a looong air gap. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Am 08.12.2014 um 18:57 schrieb Dave M: The text on the screen shots is a bit hard to read, but I think the curves told me what I wanted to know..As with most other devices, it's best to stay away from the Max figures on the datasheet. You can get the pictures by action - download and then watch them locally with the picture viewer of your choice. regards, Gerhard ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Am 08.12.2014 um 19:26 schrieb Richard (Rick) Karlquist: Please Gerhard, more details on your choke (medium size red Amidon core two 220 uH Siemens chokes). Maybe I can use it for 160 meter antennas. Siemens Chokes: yellow, 5.5mm dia, 27 mm long, a single ferrite rod with a lot of turns. They still have the SH logo, must be 20 years old 221.9 uH Q=17 at 100 KHz, measured on the 4274A impedance meter. Amidon: Red, the usual 80m material, 20.5mm o.d. 17 turns 0.5mm CuAg 1.962 uH Q=24 at 100 KHz pic of the inductors at https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The board in the background is my 5/10 MHz buffer, NIST FET doubler with 2*BF862, distribution amplifier 4 * 12 dBm based on AD8009 / LMH6702, in statu nascendi. Yesterday I drew etched the board, at the moment I'm just populating it. All 0603, sot23-5 and the like. Size is just 32 * 68 mm without the protruding SMAs. The next picture is how the Lucent RFTG-u REF1 looks with the board mounted inside. And many thanks to the people who wrote up how to power up the Lucent. It has helped me a lot. regards, Gerhard, dk4xp ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Am 29.11.2014 um 20:01 schrieb Gerhard Hoffmann: Am 29.11.2014 um 19:08 schrieb Thomas S. Knutsen: 2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Ok, I volunteer to measure the S21 of a dc-force-fed T1-1 or T4-1 next weekend, when I'm back home. (DG8SAQ VNWA and / or WG TSA-2) Really, on osc, a voltmeter and a DC source are enough. Here it is: Mini circuits T1-1T, new very old stock, still in black case, not one of the new whitish ones that turn brown in the week after soldering. 0 / 25 / 50 / 100 mA on the secondary side from Agilent 6633B dc supply. It is nice that you can directly type in the voltages or currents. But you better do not take this thing for anything that is sensitive to noise. DG8SAQ VNWA, my best DC block from PSPL because it also has the lowest lower corner. It took some experimenting to find a choke that would not modify S21 and carry the current. Finally: a medium size red Amidon core two 220uH Siemens chokes with a looong air gap. https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The low frequency corner suffers already at 25 mA. The high frequency side is unimpressed by the current. Just what one expects from a transmission line transformer that gets ferrite as an anabolicum for the low frequencies. The transformer survived 1A for a short time and did not seem to suffer from that abuse s-parameter-wise. regards, Gerhard ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Charles Steinmetz wrote: Bob wrote: My past experience with Minicircuits is that they will not give you any data the extends the spec on a part. Simply put - if you are after 1 MHz data on a part that stops at 10, they are not likely to supply it. I've had better luck getting data from them that is just not stated (as opposed to being outside a stated spec) -- for example, the nominal inductance of windings. I suspect the same might be true if someone asked, What exactly do you mean by 'DC: 30mA?' You probably wouldn't get hard data or graphs, but they might give you an idea of how they arrived at that spec. In the end, though, the only way to be sure a certain part will work in any particular circuit is to build and test it. Don't forget, you can generally keep DC out of transformer windings with shunt coupling (use an RF choke for the DC path, and capacitor couple into the transformer winding). It's an unwanted complexity, but some builders may prefer it to winding their own transformers. Best regards, Charles Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Thanks for the responses. Dave M ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Bob wrote: My past experience with Minicircuits is that they will not give you any data the extends the spec on a part. Simply put - if you are after 1 MHz data on a part that stops at 10, they are not likely to supply it. I've had better luck getting data from them that is just not stated (as opposed to being outside a stated spec) -- for example, the nominal inductance of windings. I suspect the same might be true if someone asked, What exactly do you mean by 'DC: 30mA?' You probably wouldn't get hard data or graphs, but they might give you an idea of how they arrived at that spec. In the end, though, the only way to be sure a certain part will work in any particular circuit is to build and test it. Don't forget, you can generally keep DC out of transformer windings with shunt coupling (use an RF choke for the DC path, and capacitor couple into the transformer winding). It's an unwanted complexity, but some builders may prefer it to winding their own transformers. Best regards, Charles ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Going a bit off topic, but there are decent VNA's avaible for an fair price. There is the N2PK VNA thats avaible as an board + digikey partlist and gives a 120dB dynamic range VNA from 10KHz to 50MHz, or there are the VNWA avaible ready buildt from the UK with 70-80dB dynamic range to 1.3GHz. Those are the ones I know that have true phase reading and can solve for the sign of the phase. Of course there are older HP or RS boxes, and probably others as well, and by shopping around one can get decent gear at a fair price, but with some added complexity of doing the measurments. Having an VNA helps doing measurments, but a lot of cool things can be done with a spectrum analyzer, adding a simple return loss bridge makes that into an quite decent scalar VNA. Brr. (its probably cold up here in the north :) Thomas LA3PNA. -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html PDF is an better alternative and there are always LaTeX! ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
On 11/29/2014 12:08 PM, Thomas S. Knutsen wrote: 2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Going a bit off topic, but there are decent VNA's avaible for an fair price. There is the N2PK VNA thats avaible as an board + digikey partlist and gives a 120dB dynamic range VNA from 10KHz to 50MHz, or there are the VNWA avaible ready buildt from the UK with 70-80dB dynamic range to 1.3GHz. Those are the ones I know that have true phase reading and can solve for the sign of the phase. Of course there are older HP or RS boxes, and probably others as well, and by shopping around one can get decent gear at a fair price, but with some added complexity of doing the measurments. Having an VNA helps doing measurments, but a lot of cool things can be done with a spectrum analyzer, adding a simple return loss bridge makes that into an quite decent scalar VNA. Brr. (its probably cold up here in the north :) Thomas LA3PNA. Or the DG8SAQ 1.3 GHz VNA for about £350 GBP or ~$550 I suspect this is what you are calling the VNWA available ready built from the UK with 70-80dB dynamic range to 1.3GHz. http://sdr-kits.net/VNWA3_Description.html -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Minicircuits specs
Am 29.11.2014 um 19:08 schrieb Thomas S. Knutsen: 2014-11-29 16:24 GMT+01:00 Dave M dgmin...@mediacombb.net: Yeah, that's a good way to completely avoid the issue. Since I'm the only target audience for my efforts, then I don't mind the extra components. I'm beginning to realize, as I get deeper into building my own stuff, that a VNA is quite a desireable piece of equipment. Unfortunately, I'll have to make use of my spectrum analyzer and RLC meters instead. Ok, I volunteer to measure the S21 of a dc-force-fed T1-1 or T4-1 next weekend, when I'm back home. (DG8SAQ VNWA and / or WG TSA-2) Really, on osc, a voltmeter and a DC source are enough. Brr. (its probably cold up here in the north :) Thomas LA3PNA. Not only there. I was this afternoon for 3 hours with a motor bike on the Suebian Alp in southern Germany, just 3°C above the freezing point. The last half hour was not so pleasant. regards, Gerhard, dk4xp ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
