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Hi,
Looks like NXP is trying to promote the idea of a computer controlled HF power module for defrosting food in the kitchen. Just like mass production of microwave ovens has lowered the cost of magnetrons to almost nothing, wonder if this module might be hackable to do the same for ham radio HF RF power.
Tom, wb6b
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This link specifically mentions 1.8 to 50MHZ.
Tom, wb6b
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On Mon, Jun 21, 2021 at 08:34 AM, Tom, wb6b wrote:
Looks like NXP is trying to promote the idea of a computer controlled HF power module for defrosting food in the kitchen. Just like mass production of microwave ovens has lowered the cost of magnetrons to almost nothing, wonder if this module might be hackable to do the same for ham radio HF RF power.
Tom, wb6b
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Tom
I see reference to ISM bands, to aid our non US folk this is spectrum allocated primarily for non communication apps. These are UHF or higher. And many short range unlicensed apps use this same spectrum.?
A major cost driver for a many hundred watt RF amp as the power supply, while rf heating apps don't require a clean supply.??
The challenge of QRO power amps does extend beyond the rf amplifier. LDMOS is finding its way into some ham products.?
Curt
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Power supply and capacitors.
Tom
I see reference to ISM bands, to aid our non US folk this is spectrum allocated primarily for non communication apps. These are UHF or higher. And many short range unlicensed apps use this same spectrum.?
A major cost driver for a many hundred watt RF amp as the power supply, while rf heating apps don't require a clean supply.??
The challenge of QRO power amps does extend beyond the rf amplifier. LDMOS is finding its way into some ham products.?
Curt
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There are ISM allocations in the HF and low VHF spectrum, albeit narrow ones. The 13.56 MHz frequency (bandwidth of allocation 14 KHz) used by Metcal soldering irons is the one that is probably best known to hams. Others that are available in the US include 6.78 MHz (30 KHz wide) and 40.68 MHz (40 KHz wide). There is also a 326 KHz wide allocation at 27.12 MHZ, but using that one may cause some local ire because it overlaps most of the CB radio band; you'll want to be especially careful with leakage if you use that.
Higher in the radio spectrum, there are also ISM bands at 433.94 MHZ (1.74 MHz wide, Region 1 only, NOT available in the US), 915 MHZ (26 MHz wide, Region 2 only), 2.45 GHz (100 MHz wide, used for WiFi and Bluetooth as well as microwave ovens), 5.8 GHz (150 MHz wide, used for WiFi), 24.125 GHz (250 MHz wide), 61.25 MHz (500 MHz wide), 122.5 GHz (1 GHz wide), and 245 GHz (2 GHz wide).
NXP has published a reference design but does not appear to offer manufactured modules. (So far as I can tell the design is not posted for download.) The exact frequency used is not listed in the data sheet but is shown as VHF, so it probably operates in the 40.68 MHz ISM band.
The transistors are a hair over $25 in quantity one from Mouser, which isn't bad for a 300W RF power transistor. As with most transistors in that power class, you will need a 50V power supply.
On Mon, Jun 21, 2021 at 12:35 PM Ashhar Farhan < farhanbox@...> wrote: Power supply and capacitors.
Tom
I see reference to ISM bands, to aid our non US folk this is spectrum allocated primarily for non communication apps. These are UHF or higher. And many short range unlicensed apps use this same spectrum.?
A major cost driver for a many hundred watt RF amp as the power supply, while rf heating apps don't require a clean supply.??
The challenge of QRO power amps does extend beyond the rf amplifier. LDMOS is finding its way into some ham products.?
Curt
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The GaN transistors are now used in small phone adapters. They are really inexpensive. Someone needs to figure them out.
On Mon 21 Jun, 2021, 11:12 PM Shirley Dulcey KE1L, < mark@...> wrote: There are ISM allocations in the HF and low VHF spectrum, albeit narrow ones. The 13.56 MHz frequency (bandwidth of allocation 14 KHz) used by Metcal soldering irons is the one that is probably best known to hams. Others that are available in the US include 6.78 MHz (30 KHz wide) and 40.68 MHz (40 KHz wide). There is also a 326 KHz wide allocation at 27.12 MHZ, but using that one may cause some local ire because it overlaps most of the CB radio band; you'll want to be especially careful with leakage if you use that.
Higher in the radio spectrum, there are also ISM bands at 433.94 MHZ (1.74 MHz wide, Region 1 only, NOT available in the US), 915 MHZ (26 MHz wide, Region 2 only), 2.45 GHz (100 MHz wide, used for WiFi and Bluetooth as well as microwave ovens), 5.8 GHz (150 MHz wide, used for WiFi), 24.125 GHz (250 MHz wide), 61.25 MHz (500 MHz wide), 122.5 GHz (1 GHz wide), and 245 GHz (2 GHz wide).
NXP has published a reference design but does not appear to offer manufactured modules. (So far as I can tell the design is not posted for download.) The exact frequency used is not listed in the data sheet but is shown as VHF, so it probably operates in the 40.68 MHz ISM band.
The transistors are a hair over $25 in quantity one from Mouser, which isn't bad for a 300W RF power transistor. As with most transistors in that power class, you will need a 50V power supply.
On Mon, Jun 21, 2021 at 12:35 PM Ashhar Farhan < farhanbox@...> wrote: Power supply and capacitors.
Tom
I see reference to ISM bands, to aid our non US folk this is spectrum allocated primarily for non communication apps. These are UHF or higher. And many short range unlicensed apps use this same spectrum.?
A major cost driver for a many hundred watt RF amp as the power supply, while rf heating apps don't require a clean supply.??
The challenge of QRO power amps does extend beyond the rf amplifier. LDMOS is finding its way into some ham products.?
Curt
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What about 315Mhz and 433Mhz in the U.S.? I've tested a few car remotes with my TinySA and have found both frequencies in use.
Max KG4PID
On Monday, June 21, 2021, 12:42:16 PM CDT, Shirley Dulcey KE1L <mark@...> wrote:
There are ISM allocations in the HF and low VHF spectrum, albeit narrow ones. The 13.56 MHz frequency (bandwidth of allocation 14 KHz) used by Metcal soldering irons is the one that is probably best known to hams. Others that are available in the US include 6.78 MHz (30 KHz wide) and 40.68 MHz (40 KHz wide). There is also a 326 KHz wide allocation at 27.12 MHZ, but using that one may cause some local ire because it overlaps most of the CB radio band; you'll want to be especially careful with leakage if you use that.
Higher in the radio spectrum, there are also ISM bands at 433.94 MHZ (1.74 MHz wide, Region 1 only, NOT available in the US), 915 MHZ (26 MHz wide, Region 2 only), 2.45 GHz (100 MHz wide, used for WiFi and Bluetooth as well as microwave ovens), 5.8 GHz (150 MHz wide, used for WiFi), 24.125 GHz (250 MHz wide), 61.25 MHz (500 MHz wide), 122.5 GHz (1 GHz wide), and 245 GHz (2 GHz wide).
NXP has published a reference design but does not appear to offer manufactured modules. (So far as I can tell the design is not posted for download.) The exact frequency used is not listed in the data sheet but is shown as VHF, so it probably operates in the 40.68 MHz ISM band.
The transistors are a hair over $25 in quantity one from Mouser, which isn't bad for a 300W RF power transistor. As with most transistors in that power class, you will need a 50V power supply.
On Mon, Jun 21, 2021 at 12:35 PM Ashhar Farhan < farhanbox@...> wrote: Power supply and capacitors.
Tom
I see reference to ISM bands, to aid our non US folk this is spectrum allocated primarily for non communication apps. These are UHF or higher. And many short range unlicensed apps use this same spectrum.?
A major cost driver for a many hundred watt RF amp as the power supply, while rf heating apps don't require a clean supply.??
The challenge of QRO power amps does extend beyond the rf amplifier. LDMOS is finding its way into some ham products.?
Curt
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If you look up cricketsat you will see references to using a single chip 433 MHz chip to make an expendable payload for balloon flights and the like. Our club had launched a few. Oh this band is used for military radar so its not just our repeaters and moonbounce.?
Curt
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Correct Curt,
Unfortunately many hams forget that ham radio is secondary on a lot of bands and must yield to other services and cause no interference
John
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Shirley Dulcey KE1L