tag:blogger.com,1999:blog-7590176649168185428.comments2024-03-17T14:27:31.716-04:00SolderSmoke Daily NewsBill Mearahttp://www.blogger.com/profile/07662500663603350847noreply@blogger.comBlogger7243125tag:blogger.com,1999:blog-7590176649168185428.post-22370018148933743722024-03-17T14:27:31.716-04:002024-03-17T14:27:31.716-04:00Steinmetz's successor Vladimir Karapetoff was ...Steinmetz's successor Vladimir Karapetoff was also a pretty fascinating person. He wrote an entire series of articles showing that special relativity was nothing more than hyperbolic trignometry using time as an extra dimension! KD0FNRhttps://copaseticflow.blogspot.com/2014/03/rapidity-history-and-vladimir-karapetoff.htmlnoreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-20659759640901124992024-03-15T17:18:59.479-04:002024-03-15T17:18:59.479-04:00I am looking for a couple S38E knobs 5053289032I am looking for a couple S38E knobs 5053289032Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-58748523795124666752024-03-15T17:03:26.849-04:002024-03-15T17:03:26.849-04:00From N5CFI
From N5CFI<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-17551745709763399512024-03-15T17:01:46.941-04:002024-03-15T17:01:46.941-04:00You wouldn't happen to have a couple left over...You wouldn't happen to have a couple left over knobs (2) you'd be willing to share. Just started a restoration and already over 200% of the best selling price invested. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-50454234613776555672024-03-15T10:34:32.753-04:002024-03-15T10:34:32.753-04:00This comment has been removed by the author.Walter KA4KXXhttps://www.blogger.com/profile/12914532914455704783noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-89012123837399705642024-03-15T07:11:17.777-04:002024-03-15T07:11:17.777-04:00I think you are on the right track about the high ...I think you are on the right track about the high IF frequency. Carrier suppression from the balanced mixers and whatever carrier supression the xtal filter can yield gets tougher the higher you go. That said, 23dB isn't a bad start. I'm sure it can be improved, even with the high IF.<br />Punch List:<br />1) How well matched the diodes are? Are they 1N4148's or RF Schottky's? Or Minicircuits ADE?<br />2) What does the LO spectrum look like? <br />DBM's like sine or a true square wave.<br />Not with even harmonics in the LO spectrum.<br />3) How much rejection from the XTAL filter?<br />WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-75888757488383264882024-03-14T14:43:25.851-04:002024-03-14T14:43:25.851-04:00Great thanks. I'll take a look. 73.Great thanks. I'll take a look. 73.Charlie Morris, ZL2CTMhttps://www.blogger.com/profile/02642502413959463906noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-82701600965274252852024-03-14T14:29:15.189-04:002024-03-14T14:29:15.189-04:00Yes, Charlie ZL2CTM, I think you got it right.
Bes...Yes, Charlie ZL2CTM, I think you got it right.<br />Best thing I can recommmend is :<br />https://www.qsl.net/wn2a/mouse.html<br />Download the pdf. These MOSFET's are tough, especially with protected gates. And they like short leads, gate loading for stability and good heatsinks. 73-WN2A WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-55820525724760887112024-03-14T12:57:38.062-04:002024-03-14T12:57:38.062-04:00Hi. Just confirming you typically have the two 1N4...Hi. Just confirming you typically have the two 1N4148 diodes in series with IRF510 gate, i.e., the RF drive passes through them then onto the gate? Thanks.Charlie Morris, ZL2CTMhttps://www.blogger.com/profile/02642502413959463906noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-17011411540836494512024-03-14T06:05:52.088-04:002024-03-14T06:05:52.088-04:00Bill - thanks again for recommending the BITX40 am...Bill - thanks again for recommending the BITX40 amp. I built it into the homebrew SBITX and it is working fine business! Latest blog on the project is here: https://kk4das.blogspot.com/2024/03/homebrew-sbitx-tx-modules-pa-lpf-and-mic.html<br /><br />73,<br />Dean<br />KK4DASKK4DAShttps://www.blogger.com/profile/11139781579937189613noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-52991698681695209032024-03-13T17:42:37.243-04:002024-03-13T17:42:37.243-04:00I usually use two series 1N4148's for PA Gate ...I usually use two series 1N4148's for PA Gate Protection. The 51 ohm loading reistor may provide damping and better stage K, but it does not clamp the RF excursion. I have not lost a single IRF510, RDxxxx or Polyfet part since ~1986. Prior to that, many casualties. This was better than using a zener (less capacitance).WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-51143462629110793032024-03-13T08:42:24.170-04:002024-03-13T08:42:24.170-04:00Is WFSRA still in existence ? In today's troub...Is WFSRA still in existence ? In today's troubled World a pledge only membership to such a sensible group would be a good idea. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-16100829113148371022024-03-12T14:26:56.235-04:002024-03-12T14:26:56.235-04:00Did someone say "T50-6"? Looks like them...Did someone say "T50-6"? Looks like them.WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-33600517380268151342024-03-12T12:29:04.175-04:002024-03-12T12:29:04.175-04:00I realise now. It looks like the version 2 of your...I realise now. It looks like the version 2 of your transceiver.Trevorhttps://www.blogger.com/profile/06987338653471649967noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-22128175344015207642024-03-12T12:19:11.920-04:002024-03-12T12:19:11.920-04:00Bill. What's that behind the SuperRX/TX 40 tra...Bill. What's that behind the SuperRX/TX 40 transceiver to left of the diode detection, with all the torroids? Is that part of what you picked up at the hamfest? Trevorhttps://www.blogger.com/profile/06987338653471649967noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-71055203030095492642024-03-12T09:02:13.130-04:002024-03-12T09:02:13.130-04:00Edison was a tinkerer compared to Steinmetz Edison was a tinkerer compared to Steinmetz Dickhttps://www.blogger.com/profile/07861903251605718610noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-14342774830704728132024-03-12T07:03:50.887-04:002024-03-12T07:03:50.887-04:00I gave Gemini a hypothetical situation, and asked ...I gave Gemini a hypothetical situation, and asked something I'd been thinking about for some time. If you could go back to when there was no man-made radio transmissions, with a DC receiver and a couple of friends who would transmit, being at different locations. Would a bandpass filter be necessary? If fact I asked. Would the bandpass filter be a negative? Possiblity knocking down some of the desired frequency. I didn't know how well Gemini would take my lengthy hypothetical and questions. It did well.<br /><br />"You're right, this is a cool hypothetical scenario! Here's the breakdown of the bandpass filter in your time travel ham radio situation:<br /><br />Without a Bandpass Filter:<br /><br />Yes, the receiver could still work: In the absence of any man-made radio signals, the receiver would still function even without a bandpass filter.<br /><br />Potential for Noise: However, the lack of a filter makes it susceptible to picking up all sorts of electrical noise from the environment (atmospheric noise, power lines, etc.). This noise would be present across a wide range of frequencies and could potentially mask the desired signal from your fellow time travelers.<br /><br />With a Bandpass Filter:<br /><br />Improved Signal-to-Noise Ratio: A bandpass filter tuned to the specific frequency (7.3 MHz) of the transmission would significantly improve the situation. It would allow the desired signal to pass through while attenuating everything else. This would make the signal from your companions much clearer and easier to hear amidst the background noise.<br /><br />So, the bandpass filter:<br /><br />Isn't strictly necessary for the receiver to function in this specific scenario with no competing radio signals.<br /><br />Would significantly improve the listening experience by reducing noise and making the desired signal from your fellow ham operators much clearer.<br /><br />Adding the Filter Wouldn't Attenuate the Desired Signal:<br /><br />A properly designed bandpass filter centered at 7.3 MHz would allow the signal from your companions to pass through with minimal attenuation. So, including the filter wouldn't weaken the desired signal, it would only strengthen it relative to the background noise.<br /><br />Importance of the Bandpass Filter:<br /><br />Even in a seemingly ideal situation like this, the bandpass filter plays a crucial role in enhancing the receiver's performance by:<br /><br />Simplifying reception: It makes listening easier by focusing on the specific band of interest, eliminating the need to sort through all the background noise.<br /><br />Improved sensitivity: By reducing noise, the filter effectively increases the receiver's sensitivity, allowing weaker signals to be heard more clearly.<br /><br />In conclusion, while the receiver might technically function without a bandpass filter in this particular scenario, including one would greatly improve the listening experience by filtering out unwanted noise and making communication between your time-traveling ham buddies much clearer."Trevorhttps://www.blogger.com/profile/06987338653471649967noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-85153548279257152912024-03-11T16:10:29.788-04:002024-03-11T16:10:29.788-04:00I've thought about this a long time. I'd ...I've thought about this a long time. I'd finished my BA at Urbana, IL (U of I), was working with a local rock band driving equipment back from playing in Aurora, IL (of all places). My fellow 'roadie' Chris Bland and I saw what we thought was a fire above the treeline to the west. Once we'd cleared the forrest, we pulled to the side of the road and watched an amazing light show with seemingly colored balls rolling up from swaths of green, purple and yellow. We decided it was probably flashback, excessive sleep deprivation or just weird. Years later, traveling in the polar regions, I believe what I'd seen was the Aurora Borealis. Only searching today, at 73, did I realize it was totally possible even that far south due to this phenomena in August of 1972. Shortly thereafter I returned to my natal home to begin teaching public high school. DOColtunhttps://www.blogger.com/profile/05500696169026203710noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-24370740140483834432024-03-08T04:12:52.367-05:002024-03-08T04:12:52.367-05:00It looks like Steinmetz wore a pince-nez. That'...It looks like Steinmetz wore a pince-nez. That's a known mark of a genius. Todd K7TFChttps://www.blogger.com/profile/17909491674824360102noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-13166030130894973782024-03-07T15:03:02.019-05:002024-03-07T15:03:02.019-05:00The 20's thru the 40's were productive tim...The 20's thru the 40's were productive times for the Major. My mentor (now SK) was amongst many other roles, had Armstrong as a mentor at W2XMN, Alpine. He related many stories about "the Old Man". Armstrong had a great team under him.WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-9160267555258869272024-03-07T13:52:51.694-05:002024-03-07T13:52:51.694-05:00I was looking at an Alfred Morgan radio book from ...I was looking at an Alfred Morgan radio book from 1920 where he dedicated the book to Tesla. However in a 1940 book on radio Alfred Morgan doesn't mention Tesla at all - Armstrong is mentioned several times.WB9KZYhttps://www.blogger.com/profile/13790482071874836665noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-61558587017512273962024-03-07T12:43:13.164-05:002024-03-07T12:43:13.164-05:00Chuck, WB9KZY,
The "uncertainities" are ...Chuck, WB9KZY,<br />The "uncertainities" are in the text below the photo, but I agree with your assessment as to who's who.<br />Quite a group photo! I would have preferred to see E.H. Armstrong in the photo, as so much of his circuitry inside that building made radio possible.<br /><br /><br />WN2Ahttps://www.qsl.net/wn2a/noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-76793287916446695832024-03-07T11:45:36.264-05:002024-03-07T11:45:36.264-05:00Well he can get to Disneyland fairly fast if summo...Well he can get to Disneyland fairly fast if summoned !WB9KZYhttps://www.blogger.com/profile/13790482071874836665noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-56798963882306574602024-03-07T11:36:11.727-05:002024-03-07T11:36:11.727-05:00Rumor has it that a certain Californian homebrewer...Rumor has it that a certain Californian homebrewer who is well-known to us is in fact a member of Plus Ultra! 73 Bill Bill Mearahttps://www.blogger.com/profile/07662500663603350847noreply@blogger.comtag:blogger.com,1999:blog-7590176649168185428.post-49488595449229753852024-03-07T08:31:06.069-05:002024-03-07T08:31:06.069-05:00Those identities are known, see my blog post:
htt...Those identities are known, see my blog post:<br /><br />https://wb9kzy.blogspot.com/2022/06/famous-people-meeting-or-not-plus-ultra.html<br /><br />It would have been cool if Tesla had been there, de Forest not so much :)<br /><br />Best Regards,<br />Chuck, WB9KZYWB9KZYhttps://www.blogger.com/profile/13790482071874836665noreply@blogger.com