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QDX Success story
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Excuses for a lengthier post guys. Being away from the radio for 20 or so years due to various family and business reasons (excuses?) and learned about QRP Labs, I ordered the QDX kit last summer. Although I work with electronics all my professional life, I have not been successful in building any RF device yet. Got carried away and haven't assembled the kit till recently. Last solder smoke was still hanging in the air when I booted the board to the current limited PSU. It came to life, no excessive current, nothing being too hot. Connecting the radio to a length of wire strewn across the room floor, acting as EFHW, I got decodes at 20m. Some USA and European stations, not bad at all. I brought the radio and my homemade 80-10m EFHW to a vacation place near the seashore. EFHW was simply suspended between a balcony fence and a nearby5 ?tree, sloping from about 4 to 2m above ground, best I could work out from that place. Unfortunately SWR at 80 and 30m was too high so I operated mainly on 40 and 20m. Loads of contacts from Europe, some from Africa, Asia and Americas. Heard the stations from Nova Caledonia and New Zealand but couldn't work them. For 3-4W into not that effective antenna, this is total success.Accolades for Hans' clever design and great fun from such a small radio. 72 73 Tom 9A5TT |
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Terry, I am no weakling when it comes to calling out sketchy hardware. I think folks here know that. My experience with QDX-HB has been excellent. I did make one very small modification to it, but since, it has performed flawlessly, giving me Worked All Continents several times over.? May you are? being overly harsh towards this device? JZ KJ4A? On Sun, Aug 6, 2023, 1:08 PM ve3ega <ve3ega@...> wrote: Tom, |
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John, What modification did you make to the QDX-HB? The curious amongst us would like to know. Thanks, Tony AC9QY On Sun, Aug 6, 2023 at 12:35 PM John Z <jdzbrozek@...> wrote:
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Tony? It was nothing more than a commutating diode across the offensive L14. My QDX appears to be bullet proof since then. JZ On Sun, Aug 6, 2023, 2:00 PM Tony Scaminaci <tonyscam@...> wrote:
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Hi Pierre,
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The diode simply is in parallel with the 47uH inductor L14, with the orientation shown in the photo provided by Paul W9AC. Cathode towards the power supply connection, anode to the transformer center tap. Any of the diodes he mentioned (1N4448, 1N4148, 1N914) will do a fine job of absorbing the end-of-transmission voltage spike it produces. I have used a 1N914. /g/QRPLabs/message/105256 Here you can see simulations with and without the diode present. On another thread, Evan, Hans and I explore the ability of QDX to withstand SWR. It seems to have a reputation for SWR intolerance but I think there is a case that the problem may actually be as described above. /g/QRPLabs/message/106759 Regards, JZ KJ4A On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote:
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On Mon, Aug 7, 2023 at 8:07?AM John Zbrozek <jdzbrozek@...> wrote:
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开云体育
The diode is a good idea I think. This is based not only on simulation but on measurements I have made with my scope.
In my case, the loss of two or three sets of BS170 in my two QDX units led me to try different transistors. I ran the other transistors without any failures for months. But I was curious why the BS170s would fail and the TN0106 and VN0606 would not. Yesterday
I got a new scope that allows me to see transients and I decided to look at the QDX with VN0606 transistors in it. To my surprise, the glitch at the end of a transmission was over 120 volts measured at the center tap. The transistor drains were similar. The
spike was 100ns wide at the 60 volt level. And this is into a dummy load. The transistors must just be capable of dealing with this.
I then replaced the transistors with BS170s and discovered another surprise. The spike was below 60 volts and had a broad flat (but ragged looking) top.?
Then I added the commutating diode and the spikes were gone.?
Right now my theory is that the BS170s are operating in a "make before break" mode which minimizes the di/dt. The VN0606 (and TN0106) might be in the "break before make" mode. The specific operating conditions might possibly allow the circuit to move between
these two cases and the BS170s are just not capable of handling the over-voltage spike while the other transistors can. Just a theory mind you. I have not tried yet to make measurements to verify this. Prior to these measurements, I was thinking that the opposite
would be the case, thus explaining why the VN0606/TN0106 did not fail.?
In any case, I am now running with BS170s again but with the diodes installed. We shall see how long this lasts.
Tony
AD0VC
From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...>
Sent: Monday, August 7, 2023 6:14 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
Simulations are here:
/g/QRPLabs/message/105254 JZ On Mon, Aug 7, 2023 at 8:07?AM John Zbrozek <jdzbrozek@...> wrote: > > Hi Pierre, > > The diode simply is in parallel with the 47uH inductor L14, with the > orientation shown in the photo provided by Paul W9AC. Cathode towards > the power supply connection, anode to the transformer center tap. > Any of the diodes he mentioned? (1N4448, 1N4148, 1N914) will do a fine > job of absorbing the end-of-transmission voltage spike it produces. > I have used a 1N914. > > /g/QRPLabs/message/105256 > > Here you can see simulations with and without the diode present. > > On another thread, Evan, Hans and I explore the ability of QDX to > withstand SWR. It seems to have a reputation for SWR intolerance but I > think there is a case that the problem may actually be as described > above. > > /g/QRPLabs/message/106759 > > Regards, JZ KJ4A > > On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote: > > > > Could you please elaborate: what diode, how did you connect it? A handmade schematic and a photo would be nice. > > 73 > > Pierre > > FK8IH > > |
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Tony,
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My guess is that when you were running the BS170s and seeing a flat-topped 60V you were observing avalanche breakdown of the BS170 drain. Drain-gate oxide breakdown can also happen at that voltage. The TN0106 and VN0606 also have 60V breakdown specs, but the spec is a minimum and actual breakdown may occur at substantially higher voltage. In any case, you have seen first-hand what the inductive kick looks like and what damage it is capable of inflicting. JZ KJ4A On Tue, Aug 8, 2023 at 8:01?AM mux_folder2001 <canthony15@...> wrote:
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Yes, that makes sense. I am still learning my new scope. I had it set to measure "Top" instead of "Maximum". You can see from the graticule scale that it is about 70 volts. BS170 drain picture attached (into dummy load, 9 volt build).
Tony
AD0VC
From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...>
Sent: Tuesday, August 8, 2023 6:12 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
Tony,
My guess is that when you were running the BS170s and seeing a flat-topped 60V you were observing avalanche breakdown of the BS170 drain. Drain-gate oxide breakdown can also happen at that voltage. The TN0106 and VN0606 also have 60V breakdown specs, but the spec is a minimum and actual breakdown may occur at substantially higher voltage. In any case, you have seen first-hand what the inductive kick looks like and what damage it is capable of inflicting. JZ KJ4A On Tue, Aug 8, 2023 at 8:01?AM mux_folder2001 <canthony15@...> wrote: > > The diode is a good idea I think. This is based not only on simulation but on measurements I have made with my scope. > > In my case, the loss of two or three sets of BS170 in my two QDX units led me to try different transistors. I ran the other transistors without any failures for months. But I was curious why the BS170s would fail and the TN0106 and VN0606 would not. Yesterday I got a new scope that allows me to see transients and I decided to look at the QDX with VN0606 transistors in it. To my surprise, the glitch at the end of a transmission was over 120 volts measured at the center tap. The transistor drains were similar. The spike was 100ns wide at the 60 volt level. And this is into a dummy load. The transistors must just be capable of dealing with this. > > I then replaced the transistors with BS170s and discovered another surprise. The spike was below 60 volts and had a broad flat (but ragged looking) top. > > Then I added the commutating diode and the spikes were gone. > > Right now my theory is that the BS170s are operating in a "make before break" mode which minimizes the di/dt. The VN0606 (and TN0106) might be in the "break before make" mode. The specific operating conditions might possibly allow the circuit to move between these two cases and the BS170s are just not capable of handling the over-voltage spike while the other transistors can. Just a theory mind you. I have not tried yet to make measurements to verify this. Prior to these measurements, I was thinking that the opposite would be the case, thus explaining why the VN0606/TN0106 did not fail. > > In any case, I am now running with BS170s again but with the diodes installed. We shall see how long this lasts. > > Tony > AD0VC > > ________________________________ > From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...> > Sent: Monday, August 7, 2023 6:14 AM > To: [email protected] <[email protected]> > Subject: Re: [QRPLabs] QDX Success story > > Simulations are here: > > /g/QRPLabs/message/105254 > > JZ > > On Mon, Aug 7, 2023 at 8:07?AM John Zbrozek <jdzbrozek@...> wrote: > > > > Hi Pierre, > > > > The diode simply is in parallel with the 47uH inductor L14, with the > > orientation shown in the photo provided by Paul W9AC. Cathode towards > > the power supply connection, anode to the transformer center tap. > > Any of the diodes he mentioned? (1N4448, 1N4148, 1N914) will do a fine > > job of absorbing the end-of-transmission voltage spike it produces. > > I have used a 1N914. > > > > /g/QRPLabs/message/105256 > > > > Here you can see simulations with and without the diode present. > > > > On another thread, Evan, Hans and I explore the ability of QDX to > > withstand SWR. It seems to have a reputation for SWR intolerance but I > > think there is a case that the problem may actually be as described > > above. > > > > /g/QRPLabs/message/106759 > > > > Regards, JZ KJ4A > > > > On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote: > > > > > > Could you please elaborate: what diode, how did you connect it? A handmade schematic and a photo would be nice. > > > 73 > > > Pierre > > > FK8IH > > > > > > > > > |
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From: [email protected] <[email protected]> on behalf of mux_folder2001 <canthony15@...>
Sent: Tuesday, August 8, 2023 6:36 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
Yes, that makes sense. I am still learning my new scope. I had it set to measure "Top" instead of "Maximum". You can see from the graticule scale that it is about 70 volts. BS170 drain picture attached (into dummy load, 9 volt build).
Tony
AD0VC
From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...>
Sent: Tuesday, August 8, 2023 6:12 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
Tony,
My guess is that when you were running the BS170s and seeing a flat-topped 60V you were observing avalanche breakdown of the BS170 drain. Drain-gate oxide breakdown can also happen at that voltage. The TN0106 and VN0606 also have 60V breakdown specs, but the spec is a minimum and actual breakdown may occur at substantially higher voltage. In any case, you have seen first-hand what the inductive kick looks like and what damage it is capable of inflicting. JZ KJ4A On Tue, Aug 8, 2023 at 8:01?AM mux_folder2001 <canthony15@...> wrote: > > The diode is a good idea I think. This is based not only on simulation but on measurements I have made with my scope. > > In my case, the loss of two or three sets of BS170 in my two QDX units led me to try different transistors. I ran the other transistors without any failures for months. But I was curious why the BS170s would fail and the TN0106 and VN0606 would not. Yesterday I got a new scope that allows me to see transients and I decided to look at the QDX with VN0606 transistors in it. To my surprise, the glitch at the end of a transmission was over 120 volts measured at the center tap. The transistor drains were similar. The spike was 100ns wide at the 60 volt level. And this is into a dummy load. The transistors must just be capable of dealing with this. > > I then replaced the transistors with BS170s and discovered another surprise. The spike was below 60 volts and had a broad flat (but ragged looking) top. > > Then I added the commutating diode and the spikes were gone. > > Right now my theory is that the BS170s are operating in a "make before break" mode which minimizes the di/dt. The VN0606 (and TN0106) might be in the "break before make" mode. The specific operating conditions might possibly allow the circuit to move between these two cases and the BS170s are just not capable of handling the over-voltage spike while the other transistors can. Just a theory mind you. I have not tried yet to make measurements to verify this. Prior to these measurements, I was thinking that the opposite would be the case, thus explaining why the VN0606/TN0106 did not fail. > > In any case, I am now running with BS170s again but with the diodes installed. We shall see how long this lasts. > > Tony > AD0VC > > ________________________________ > From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...> > Sent: Monday, August 7, 2023 6:14 AM > To: [email protected] <[email protected]> > Subject: Re: [QRPLabs] QDX Success story > > Simulations are here: > > /g/QRPLabs/message/105254 > > JZ > > On Mon, Aug 7, 2023 at 8:07?AM John Zbrozek <jdzbrozek@...> wrote: > > > > Hi Pierre, > > > > The diode simply is in parallel with the 47uH inductor L14, with the > > orientation shown in the photo provided by Paul W9AC. Cathode towards > > the power supply connection, anode to the transformer center tap. > > Any of the diodes he mentioned? (1N4448, 1N4148, 1N914) will do a fine > > job of absorbing the end-of-transmission voltage spike it produces. > > I have used a 1N914. > > > > /g/QRPLabs/message/105256 > > > > Here you can see simulations with and without the diode present. > > > > On another thread, Evan, Hans and I explore the ability of QDX to > > withstand SWR. It seems to have a reputation for SWR intolerance but I > > think there is a case that the problem may actually be as described > > above. > > > > /g/QRPLabs/message/106759 > > > > Regards, JZ KJ4A > > > > On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote: > > > > > > Could you please elaborate: what diode, how did you connect it? A handmade schematic and a photo would be nice. > > > 73 > > > Pierre > > > FK8IH > > > > > > > > > |
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That's quite a punch, Tony! Consider this: It gets worse when the load is at a low impedance.? The drain currents go up sharply, and then so does the energy stored in the inductor, as the square of the current.? That magnifies the danger of the low Z/ high SWR case. JZ On Tue, Aug 8, 2023, 8:40 AM mux_folder2001 <canthony15@...> wrote:
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Yes, exactly. This was the case with my antenna during rainy weather as measured with my nanovna.?
So, the manufacturer of these VN0606 and TN0106 may be binning 100 volt parts as 60 volts, maybe due to some other parameter. Who knows.?
Anyway, I am hopeful that time will demonstrate that the diode is all that I need.?
One thing to note is that the idea that avalanche for even a very short time will kill the device is not always the case. It appears to me that the BS170 is being hammered at every EOT into 50 ohms.?
Tony
From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...>
Sent: Tuesday, August 8, 2023 7:16 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
That's quite a punch, Tony!
Consider this: It gets worse when the load is at a low impedance.?
The drain currents go up sharply, and then so does the energy stored in the inductor, as the square of the current.?
That magnifies the danger of the low Z/ high SWR case.
JZ
On Tue, Aug 8, 2023, 8:40 AM mux_folder2001 <canthony15@...> wrote:
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Yes, agreed!
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I think the fatal mechanism though is gate oxide punch through rather than avalanche, and that avalanche, if it is the lower voltage condition, actually somewhat protects the transistor by putting a higher failure energy demand on the inductor. The problem is, it can go either way. I have seen "walking wounded" failures of the BS170s where it is clear they are leaking drain current through a gate oxide pinhole and into the 74act08 driver chip. Things still work, but with degradation. It all depends on how big the punchthrough is and where it is. Large enough and the driver chip dies along with the BS170. JZ On Tue, Aug 8, 2023 at 9:31?AM mux_folder2001 <canthony15@...> wrote:
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From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...>
Sent: Tuesday, August 8, 2023 7:48 AM To: [email protected] <[email protected]> Subject: Re: [QRPLabs] QDX Success story ?
Yes, agreed!
I think the fatal mechanism though is gate oxide punch through rather than avalanche, and that avalanche, if it is the lower voltage condition, actually somewhat protects the transistor by putting a higher failure energy demand on the inductor. The problem is, it can go either way. I have seen "walking wounded" failures of the BS170s where it is clear they are leaking drain current through a gate oxide pinhole and into the 74act08 driver chip. Things still work, but with degradation. It all depends on how big the punchthrough is and where it is. Large enough and the driver chip dies along with the BS170. JZ On Tue, Aug 8, 2023 at 9:31?AM mux_folder2001 <canthony15@...> wrote: > > Yes, exactly. This was the case with my antenna during rainy weather as measured with my nanovna. > > So, the manufacturer of these VN0606 and TN0106 may be binning 100 volt parts as 60 volts, maybe due to some other parameter. Who knows. > > Anyway, I am hopeful that time will demonstrate that the diode is all that I need. > > One thing to note is that the idea that avalanche for even a very short time will kill the device is not always the case. It appears to me that the BS170 is being hammered at every EOT into 50 ohms. > > Tony > ________________________________ > From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...> > Sent: Tuesday, August 8, 2023 7:16 AM > To: [email protected] <[email protected]> > Subject: Re: [QRPLabs] QDX Success story > > That's quite a punch, Tony! > > Consider this: It gets worse when the load is at a low impedance. > > The drain currents go up sharply, and then so does the energy stored in the inductor, as the square of the current. > That magnifies the danger of the low Z/ high SWR case. > > JZ > > On Tue, Aug 8, 2023, 8:40 AM mux_folder2001 <canthony15@...> wrote: > > For good measure, here is the VN0606 drain picture. > > Tony > > ________________________________ > From: [email protected] <[email protected]> on behalf of mux_folder2001 <canthony15@...> > Sent: Tuesday, August 8, 2023 6:36 AM > To: [email protected] <[email protected]> > Subject: Re: [QRPLabs] QDX Success story > > Yes, that makes sense. I am still learning my new scope. I had it set to measure "Top" instead of "Maximum". You can see from the graticule scale that it is about 70 volts. BS170 drain picture attached (into dummy load, 9 volt build). > > Tony > AD0VC > ________________________________ > From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...> > Sent: Tuesday, August 8, 2023 6:12 AM > To: [email protected] <[email protected]> > Subject: Re: [QRPLabs] QDX Success story > > Tony, > > My guess is that when you were running the BS170s and seeing a > flat-topped 60V you were observing avalanche breakdown of the BS170 > drain. Drain-gate oxide breakdown can also happen at that voltage. > > The TN0106 and VN0606 also have 60V breakdown specs, but the spec is a > minimum and actual breakdown may occur at substantially higher > voltage. > > In any case, you have seen first-hand what the inductive kick looks > like and what damage it is capable of inflicting. > > JZ KJ4A > > On Tue, Aug 8, 2023 at 8:01?AM mux_folder2001 <canthony15@...> wrote: > > > > The diode is a good idea I think. This is based not only on simulation but on measurements I have made with my scope. > > > > In my case, the loss of two or three sets of BS170 in my two QDX units led me to try different transistors. I ran the other transistors without any failures for months. But I was curious why the BS170s would fail and the TN0106 and VN0606 would not. Yesterday I got a new scope that allows me to see transients and I decided to look at the QDX with VN0606 transistors in it. To my surprise, the glitch at the end of a transmission was over 120 volts measured at the center tap. The transistor drains were similar. The spike was 100ns wide at the 60 volt level. And this is into a dummy load. The transistors must just be capable of dealing with this. > > > > I then replaced the transistors with BS170s and discovered another surprise. The spike was below 60 volts and had a broad flat (but ragged looking) top. > > > > Then I added the commutating diode and the spikes were gone. > > > > Right now my theory is that the BS170s are operating in a "make before break" mode which minimizes the di/dt. The VN0606 (and TN0106) might be in the "break before make" mode. The specific operating conditions might possibly allow the circuit to move between these two cases and the BS170s are just not capable of handling the over-voltage spike while the other transistors can. Just a theory mind you. I have not tried yet to make measurements to verify this. Prior to these measurements, I was thinking that the opposite would be the case, thus explaining why the VN0606/TN0106 did not fail. > > > > In any case, I am now running with BS170s again but with the diodes installed. We shall see how long this lasts. > > > > Tony > > AD0VC > > > > ________________________________ > > From: [email protected] <[email protected]> on behalf of John Z <jdzbrozek@...> > > Sent: Monday, August 7, 2023 6:14 AM > > To: [email protected] <[email protected]> > > Subject: Re: [QRPLabs] QDX Success story > > > > Simulations are here: > > > > /g/QRPLabs/message/105254 > > > > JZ > > > > On Mon, Aug 7, 2023 at 8:07?AM John Zbrozek <jdzbrozek@...> wrote: > > > > > > Hi Pierre, > > > > > > The diode simply is in parallel with the 47uH inductor L14, with the > > > orientation shown in the photo provided by Paul W9AC. Cathode towards > > > the power supply connection, anode to the transformer center tap. > > > Any of the diodes he mentioned? (1N4448, 1N4148, 1N914) will do a fine > > > job of absorbing the end-of-transmission voltage spike it produces. > > > I have used a 1N914. > > > > > > /g/QRPLabs/message/105256 > > > > > > Here you can see simulations with and without the diode present. > > > > > > On another thread, Evan, Hans and I explore the ability of QDX to > > > withstand SWR. It seems to have a reputation for SWR intolerance but I > > > think there is a case that the problem may actually be as described > > > above. > > > > > > /g/QRPLabs/message/106759 > > > > > > Regards, JZ KJ4A > > > > > > On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote: > > > > > > > > Could you please elaborate: what diode, how did you connect it? A handmade schematic and a photo would be nice. > > > > 73 > > > > Pierre > > > > FK8IH > > > > > > > > > > > > > > > > > > > > > > |
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An excellent note.
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Subtitle: "How to make Magic Blue Smoke even when you think you are safe." JZ KJ4A On Sat, Aug 12, 2023 at 1:24?PM mux_folder2001 <canthony15@...> wrote:
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开云体育On QMX, it's been suggested to put a 47v zener from drain to ground on each side of the output transformer, to protect against high SWR over voltage. Wouldn't that also obviate the need for that commutating diode? Paul On 8/24/23 07:39, Jonathan Halterman
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I read this with interest a few weeks ago and would be interested in Hans' thoughts on a commutating diode across L14 and wondering if perhaps there might be a future revision to the QDX? |
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One thing that comes to mind when comparing the inductive spike at the drains between the TN/VN*06 and the BS170 - you saw a 120V spike with the former compared to 60V with the BS170 - is that the BS170 is not turned on all the way with a 5V drive while the *06 devices are more strongly turned on due to their lower gate thresholds. This was the primary reason I suggested the *06/*10 FETs. The lower gate threshold of the *06 FETs results in a higher drain current which builds a larger magnetic field in the inductor and therefore a larger inductive kick when the FET turns off. Regardless of what physical limitations in the BS170 are clamping the spikes at 60V, the *06 devices will produce a larger spike and will also produce more power output because they’re simply better switching transistors than the BS170 for the existing PA design. They also dissipate less power than the BS170 because Vds is smaller when they’re on. In any event, I certainly would not recommend allowing a spike over 60V so the clamp diode is a good addition. Long story short and with all other things being equal, the TN/VN*06 transistors are better suited to the existing PA design than the BS170. Others on this forum have found this swap to be very beneficial and I’ve yet to hear a complaint of any *06 devices blowing. Tony - AC9QY On Tue, Aug 8, 2023 at 7:01 AM mux_folder2001 <canthony15@...> wrote:
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Paul,
QMX has no spike voltage issue at end of transmission because of the built-in wave shaping system. Regarding Zeners for QDX, they may provide some protection against the hi-Z SWR case, but they are not a good solution to the inductive spike problem. At the moment the BS170 transistors turn off, there is approximately an amp +/- of current flowing through L14. That current will now go to the Zeners, where it most likely will be shared unequally as they are not identical. The datasheet for 1N4756A shows a maximum current of 95 mA. The voltage at the BS170 drains will be well above the Zener voltage of 47 volts, as that high current and the Zener diode resistance conspire to elevate it well above the BS170 breakdown spec. The diode instantaneous power will be very high, perhaps as much as 75 watts each for a very brief time.? These are not healthy conditions, either for the Zener diodes or the transistors. A commutating diode across L14 which is capable of handling the coil's current avoids all these problems. JZ KJ4A |
Pierre - FK8IH
Paul - AI7JR
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