For you designer builders...
开云体育I attended an online seminar/ instruction/ discussions today (with a friend of mine) regarding power supply devices and I learned a lot.? First off 7805 voltage regulators are very noisy… in fact generate 40nV of noise at best.? That noise gets into the A/D and D/A so with a 24 bit A/D with resolution of 298 nV (on 5V… its worse on 3V being 179nv)m that 40nV gives you a much higher noise floor and less dynamic range.? Buck/boost regulators are far worse.? There are ultra-low noise regulators that should be used with projects that use high resolution A/D and D/A converters in radios… like the LT3042 and LT3042 that are about 80db below a linear regular in noise generation.?? They are about 10x more expensive than the 7805 series regulators, but are critical to low noise floors. ? As a result, when I get time (and that may be years from now)… I’ll make some measurements on the T41 hardware for absolute noise floor and then sub in these low noise regulators and see what I measure. [nb. my thought would be to make small vertical boards with these low noise regulators on them… which are flat packs… to simply replace the 7805 type regulator with heatsink]. ? Lots to do. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? |
开云体育ARG!!!? LT3042 and LT3045… ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of K9HZ
Sent: Wednesday, February 12, 2025 11:33 AM To: [email protected] Subject: [AmateurRadioBuilders] For you designer builders... ? I attended an online seminar/ instruction/ discussions today (with a friend of mine) regarding power supply devices and I learned a lot.? First off 7805 voltage regulators are very noisy… in fact generate 40nV of noise at best.? That noise gets into the A/D and D/A so with a 24 bit A/D with resolution of 298 nV (on 5V… its worse on 3V being 179nv)m that 40nV gives you a much higher noise floor and less dynamic range.? Buck/boost regulators are far worse.? There are ultra-low noise regulators that should be used with projects that use high resolution A/D and D/A converters in radios… like the LT3042 and LT3042 that are about 80db below a linear regular in noise generation.?? They are about 10x more expensive than the 7805 series regulators, but are critical to low noise floors. ? As a result, when I get time (and that may be years from now)… I’ll make some measurements on the T41 hardware for absolute noise floor and then sub in these low noise regulators and see what I measure. [nb. my thought would be to make small vertical boards with these low noise regulators on them… which are flat packs… to simply replace the 7805 type regulator with heatsink]. ? Lots to do. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? |
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They seem to have a large price drop (~25%) when you go from 1 to 10 units...almost in half when you buy 25 units. Maybe pre-orders would help you cut costs. Jack, W8TEE
On Wednesday, February 12, 2025 at 12:35:25 PM EST, K9HZ <bill@...> wrote:
ARG!!!? LT3042 and LT3045… ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of K9HZ
Sent: Wednesday, February 12, 2025 11:33 AM To: [email protected] Subject: [AmateurRadioBuilders] For you designer builders... ? I attended an online seminar/ instruction/ discussions today (with a friend of mine) regarding power supply devices and I learned a lot.? First off 7805 voltage regulators are very noisy… in fact generate 40nV of noise at best.? That noise gets into the A/D and D/A so with a 24 bit A/D with resolution of 298 nV (on 5V… its worse on 3V being 179nv)m that 40nV gives you a much higher noise floor and less dynamic range.? Buck/boost regulators are far worse.? There are ultra-low noise regulators that should be used with projects that use high resolution A/D and D/A converters in radios… like the LT3042 and LT3042 that are about 80db below a linear regular in noise generation.?? They are about 10x more expensive than the 7805 series regulators, but are critical to low noise floors. ? As a result, when I get time (and that may be years from now)… I’ll make some measurements on the T41 hardware for absolute noise floor and then sub in these low noise regulators and see what I measure. [nb. my thought would be to make small vertical boards with these low noise regulators on them… which are flat packs… to simply replace the 7805 type regulator with heatsink]. ? Lots to do. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? -- Jack, W8TEE |
开云体育And these are not the kind of parts that even the most skilled builder would want to solder onto a board.?? If I ever do this, the boards will come pre-populated.? They are 3mm x 3mm.? YIKES! ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of Jack, W8TEE via groups.io
Sent: Wednesday, February 12, 2025 11:47 AM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? They seem to have a large price drop (~25%) when you go from 1 to 10 units...almost in half when you buy 25 units. Maybe pre-orders would help you cut costs. ? Jack, W8TEE ? On Wednesday, February 12, 2025 at 12:35:25 PM EST, K9HZ <bill@...> wrote: ? ? ARG!!!? LT3042 and LT3045… ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of K9HZ ? I attended an online seminar/ instruction/ discussions today (with a friend of mine) regarding power supply devices and I learned a lot.? First off 7805 voltage regulators are very noisy… in fact generate 40nV of noise at best.? That noise gets into the A/D and D/A so with a 24 bit A/D with resolution of 298 nV (on 5V… its worse on 3V being 179nv)m that 40nV gives you a much higher noise floor and less dynamic range.? Buck/boost regulators are far worse.? There are ultra-low noise regulators that should be used with projects that use high resolution A/D and D/A converters in radios… like the LT3042 and LT3042 that are about 80db below a linear regular in noise generation.?? They are about 10x more expensive than the 7805 series regulators, but are critical to low noise floors. ? As a result, when I get time (and that may be years from now)… I’ll make some measurements on the T41 hardware for absolute noise floor and then sub in these low noise regulators and see what I measure. [nb. my thought would be to make small vertical boards with these low noise regulators on them… which are flat packs… to simply replace the 7805 type regulator with heatsink]. ? Lots to do. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ?
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开云体育I think that depends on the circumstances but yes the low noise parts make a much bigger difference. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of glenn percy via groups.io
Sent: Sunday, February 16, 2025 7:03 PM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? Hi Bill Not sure how true this is but apparently LM317 style regulators are better than the LM7805's.?? Not as good as a dedicated low noise part though for sure. ? glenn vk3ep ? |
开云体育Yep that’s the ticket!? I had in the back of my brain designing a board identical to that little guy… that would simply replace the regulator and there it is!? ? I think I could do it for less than half that cost though…? If time permits, I’ll give making it a try.? It certainly would be a major improvement for us radio guys that use A/D and D/A converters in our radios! ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of John Bennett via groups.io
Sent: Monday, February 17, 2025 10:28 AM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? Great idea - a French DIY audio company offers these for sale (not cheap): ? ? John Bennett AE0AM ? ? |
开云体育Yep.? I can get then for the same price here but I must order them for future delivery…? Yeah.? Make some small boards and… Fanny and Bob are both in the house! ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of mk3msm via groups.io
Sent: Monday, February 17, 2025 10:51 AM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? and in 1K lots they cost $3.37 each On 17/02/2025 16:28, John Bennett via groups.io wrote:
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开云体育Kind-of, yes! ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of John Bennett via groups.io
Sent: Monday, February 17, 2025 11:40 AM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? A great thing about the LT3045 is that you can parallel them for higher current and even lower noise (with careful PCB layout). John Bennett AE0AM |
开云体育Have you ever used one from aliexpress?? Interested to hear if they actually work… because they sell those replacements for less than what I can buy just the chips for. ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of glenn percy via groups.io
Sent: Monday, February 17, 2025 7:41 PM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? They pop up on Aliexpress at about US$4 |
开云体育Yeah that’s where I am too… ? ? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ? From: [email protected] <[email protected]> On Behalf Of Phil Taylor via groups.io
Sent: Wednesday, February 19, 2025 9:01 PM To: [email protected] Subject: Re: [AmateurRadioBuilders] For you designer builders... ? I was looking into this when I purchased all my parts. ? A lot of these devices like the Aliexpress ones don't have the matching pinouts for LMx17 - the Vi and Vo are wrong. The 78xx versions seem ok. The devices from that Audiophonics site seem ok but there is no actual datasheet - so are they?? Besides the are way expensive at 25 euro.? ? So be careful what you buy ready built. ? I think building your own is the way to go. ? ? Regards? Phil VK2KKZ On Tue, Feb 18, 2025 at 01:57 PM, K9HZ wrote:
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K9HZ
Jack, W8TEE
JP McGinley