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One possible alternative for a S/H ADC (12bit, 2 input, 2.5V input, 5V Vcc, etc) is the older ADC12130. Is there a newer and less expensive version out there ?
73 Kees K5BCQ
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Could maybe build a S/H from a 2n7002 and a cap, hard to beat the price.
Not sure it would perform very well, depends on the input impedance of your ADC?
(or perhaps of some voltage follower you buffer it with).
Has the advantage of being very new, it's a fresh S/H as each kit gets built up.
You may only need one S/H, depends on how that ADC gets triggered to sample.
Would want to trigger the S/H for the 2'd channel at the same time as you trigger the first ADC channel.
If the ADC is only triggered by an i2c register write, probably need two S/H's.
Jerry, KE7ER
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On Thu, May 10, 2018 at 08:23 am, Kees T wrote:
One possible alternative for a S/H ADC (12bit, 2 input, 2.5V input, 5V Vcc, etc) is the older ADC12130. Is there a newer and less expensive version out there ?
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I think the MCP 3202 is 12 bit w/ S&H and pretty cheap...
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it:
email:??bill@... ?
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On May 10, 2018, at 10:23 AM, Kees T < windy10605@...> wrote: One possible alternative for a S/H ADC (12bit, 2 input, 2.5V input, 5V Vcc, etc) is the older ADC12130. Is there a newer and less expensive version out there ?
73 Kees K5BCQ
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Possible.
SPI interface, so 4 new Nano pins.? ? Could be OK if display goes to SPI.
Two channels but only one internal S/H.? However SPI is fast enough to ignore the lag between channels.
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On Thu, May 10, 2018 at 09:06 am, K9HZ wrote:
I think the MCP 3202 is 12 bit w/ S&H and pretty cheap...
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As far as a quick and easy "Antenna Confirmation", I still like that little circuit Don, ND6T, came up with....and maybe others out there. Just a broadband noise generator and tune for the null with the receiver part of the Transceiver. No meters, no digital values to convert (which may or may not be correct) ....just a subjectively monitored "noise dip" as you tune the receiver while the noise generator is activated. If you are in the "dip", great, hit the PTT, ......if the dip is off frequency, just retune until it's on frequency. A bit different, a bit unusual, but very inexpensive and located under the covers of the UBITX with no Nano code change required.?
I've discussed installing it under the covers (vs externally) with Don and he tried it on his BITX-40 and says it works well.?
73 Kees K5BCQ
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Bill,
Yes, that's much better ...MCP3202. Thanks !? I figure SPI is coming anyway because the little inexpensive (~$8) 2.8" TFTs are SPI and would make a great readout (and use existing 4 LCD pins on the Raduino interface ....hint,hint. The ones DuWayne used).?
73 Kees K5BCQ?
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As i recall from memory there are others in that series of MCP3xxx that have dual S&H and maybe 4 channels... and for some reason cheaper than the 3202? ?Maybe 3204? (Working without datasheets here)
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it:
email:??bill@... ?
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On May 10, 2018, at 11:17 AM, Jerry Gaffke via Groups.Io < jgaffke@...> wrote: Possible. SPI interface, so 4 new Nano pins.? ? Could be OK if display goes to SPI. Two channels but only one internal S/H.? However SPI is fast enough to ignore the lag between channels. On Thu, May 10, 2018 at 09:06 am, K9HZ wrote:
I think the MCP 3202 is 12 bit w/ S&H and pretty cheap...
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We're also using SPI on the 5" and 7" displays.
Jack, W8TEE
On Thursday, May 10, 2018, 12:36:04 PM EDT, Kees T <windy10605@...> wrote:
Bill,
Yes, that's much better ...MCP3202. Thanks !? I figure SPI is coming anyway because the little inexpensive (~$8) 2.8" TFTs are SPI and would make a great readout (and use existing 4 LCD pins on the Raduino interface ....hint,hint. The ones DuWayne used).?
73 Kees K5BCQ?
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DuWayne's note was? ? /g/BITX20/message/47837? ? We need a better indexing to find "stuff" with 2000 messages per month.? 73 Kees K5BCQ
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Might as well publish your "JackAl" FDIM presentation, Jack. We can all "proofread" it for you.?
73 Kees K5BCQ
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Actually, JackAl has very little to do with my FDIM presentation, which is on homebrewing. The JackAl board will be shown at the Show-and-Tell, which I think is Friday evening.
Jack, W8TEE
On Thursday, May 10, 2018, 12:47:18 PM EDT, Kees T <windy10605@...> wrote:
Might as well publish your "JackAl" FDIM presentation, Jack. We can all "proofread" it for you.?
73 Kees K5BCQ
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You could also use 2x MCP3221 parts with an I2C interface and you would have 2x S/H,12 bits and 2x SOT-23 package for even fewer $
73 Kees K5BCQ.
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I don't think that's a win.
The only way to tell the S/H to take a sample is to communicate via the i2c bus.
I suppose you could have two i2c buses, drive them simultaneously when taking a sample,
then read them out individually.? But this is getting messy.
?
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On Thu, May 10, 2018 at 10:05 am, Kees T wrote:
You could also use 2x MCP3221 parts with an I2C interface and you would have 2x S/H,12 bits and 2x SOT-23 package for even fewer $
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Yeah thats the one i was thinking of...
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it:
email:??bill@... ?
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On May 10, 2018, at 12:05 PM, Kees T < windy10605@...> wrote: You could also use 2x MCP3221 parts with an I2C interface and you would have 2x S/H,12 bits and 2x SOT-23 package for even fewer $
73 Kees K5BCQ.
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There is a trick i use for this. ?I stack all of the S/H enables on one bus (one processor pin and it can be multiplexed with a whole host of other events). Then you have all of your samples taken at the same time. ?Then i casually go read the S/H signals and resolve them using a muxed A/D. Build the data and display it when its all together. ?It works quite nicely this way. ?
Dr.?William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton - J68HZ Soufriere, St. Lucia W.I. Rent it:
email:??bill@... ?
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On May 10, 2018, at 12:17 PM, Jerry Gaffke via Groups.Io < jgaffke@...> wrote: I don't think that's a win. The only way to tell the S/H to take a sample is to communicate via the i2c bus. I suppose you could have two i2c buses, drive them simultaneously when taking a sample, then read them out individually.? But this is getting messy. ? On Thu, May 10, 2018 at 10:05 am, Kees T wrote:
You could also use 2x MCP3221 parts with an I2C interface and you would have 2x S/H,12 bits and 2x SOT-23 package for even fewer $
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Jack,
I for one am excited to hear about the JackAL, also the upcoming autotuner project.
Regarding FDIM, has anyone information on the live streaming of the seminars?
73, Kevin KB3OMM
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Jack,
Hows about the JackAl board accompanying you to vendor night?? Unfortunately, we will be headed back home Friday afternoon.
73,
Pat AA4PG
http://www.cahabatechnology.com/aa4pg.html
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Actually, JackAl has very little to do with my FDIM presentation, which is on homebrewing. The JackAl board will be shown at the Show-and-Tell, which I think is Friday evening.
Jack, W8TEE
On Thursday, May 10, 2018, 12:47:18 PM EDT, Kees T <windy10605@...> wrote:
Might as well publish your "JackAl" FDIM presentation, Jack. We can all "proofread" it for you.?
73 Kees K5BCQ
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K9HZ