tag:blogger.com,1999:blog-3380839830287420877.post3474032348480603956..comments2024-03-26T07:29:36.610-07:00Comments on VE7SL - Steve - Amateur Radio Blog: 49'er & Fake TransistorsSteve McDonaldhttp://www.blogger.com/profile/06229640265009249231noreply@blogger.comBlogger13125tag:blogger.com,1999:blog-3380839830287420877.post-80584247204812940372016-06-23T16:30:46.746-07:002016-06-23T16:30:46.746-07:00Thanks for posting this tidbit, Steve. I stumbled ...Thanks for posting this tidbit, Steve. I stumbled across it while assembling the Forty-9er-with-VFO mod that RickG linked to above. I was testing the transmit functionality into a dummy load, when I heard a soft "pop" in my earphones and the unit suddenly began receiving AM broadcast stations. I discovered that the D882 final had blown.<br /><br />I replaced the D882 with a BD139 as you referenced, and now get about 3W out with 12V in.<br /><br />Jeff, KK9JEF<br />kk9jef.wordpress.comAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-62715789405174717622016-06-14T16:53:21.481-07:002016-06-14T16:53:21.481-07:00Just found the an assembly guide at the following ...Just found the an assembly guide at the following link: http://www.farrukhzia.com/k2zia/Purdum0316-QST-in-Depth-AssemblyManual.pdf<br /><br />Has color schematic and includes the instructions for the toroids.RickGhttps://www.blogger.com/profile/06750250835131755502noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-59931045501522430772016-06-14T16:21:03.440-07:002016-06-14T16:21:03.440-07:00Michael,
With regard to the toroids, the schematic...Michael,<br />With regard to the toroids, the schematic with mine has toroid sketches to the side, with notes in Chinese that reference the wire diameter and, I'm guessing, the number of turns. The note for L3 (FT37-43) shows 11, and for L4 (T37-2) it shows 16.<br /><br />Since I do not read Chinese, and haven't built the kit yet, use my comment at your own risk.RickGhttps://www.blogger.com/profile/06750250835131755502noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-3805170063443511612016-05-20T15:59:25.121-07:002016-05-20T15:59:25.121-07:00I don't think it would work on 21 MHz with the...I don't think it would work on 21 MHz with the supplied transistors .... my one only<br />gives 250 mW output on 7.023 MHz. <br /><br />73, de Graham, G3XTZ.Anonymoushttps://www.blogger.com/profile/03440161422727285331noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-9116759260917432432016-05-01T09:42:32.069-07:002016-05-01T09:42:32.069-07:00Dear friends, is it enough to change xtals to 21MH...Dear friends, is it enough to change xtals to 21MHz and low pass filter capacitors and inductance to 2x100pF plus 0,38uH to get it going on 15m<br />band?<br /><br />Thx NoroAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-12134830144041796292016-04-28T13:31:15.916-07:002016-04-28T13:31:15.916-07:00Michael - I have not built one so can't tell y...Michael - I have not built one so can't tell you. I do recall seeing a schematic / instructions that someone had put together here on the web. Perhaps a Google search will turn it up. The Yahoo GQRP Group has much discussion regarding this so that would be a good starting place. As well, try and find a schematic of the 'original' (U.S. kit) 49er as it is probably very similar.Steve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-35345468974902917892016-04-28T12:01:10.790-07:002016-04-28T12:01:10.790-07:00I just bought one of these Chinese 49ers. Will con...I just bought one of these Chinese 49ers. Will consider the substitute values you mention. Thing doesn't come with instructions. I can muddle through it though. Only one question. How many turns of wire do the toriods take.Anonymoushttps://www.blogger.com/profile/17856788780332914515noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-83751792426390934362016-04-13T16:54:43.587-07:002016-04-13T16:54:43.587-07:00For those interested, the March 2016 issue of the ...For those interested, the March 2016 issue of the ARRL publication QST has an interesting article on the Forty-9er and a VFO modification that eliminates the crystal frequency control and uses an Arduino Nano microprocessor and an AD9850 signal generator to build a CW unit that can access the entire 40 meter band. I am in the process of building one now. The article has links to detailed modification and assembly guides. The modifications are based on the DDS VFO project in the book Arduino Projects for Amatuer Radio by Jack Purdum and Dennis Kidder. I have a copy of the book and would highly reccomend it also. 73s KG5MPD.Anonymoushttps://www.blogger.com/profile/12624004273921416969noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-60285211793961513472016-02-23T15:03:26.485-08:002016-02-23T15:03:26.485-08:00Chris/Jan
I just got a forty-9er from china for $1...Chris/Jan<br />I just got a forty-9er from china for $11. I am looking for good instructions and/or schematics. As to your question, regarding the "spurious" oscillation, it seems that the local oscillator is constantly running. That is probably what you hear.<br />Wish me luck<br />Joe W3TTTJoe Cottonhttps://www.blogger.com/profile/11198759062560374846noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-41807711985656288232015-10-21T10:43:41.606-07:002015-10-21T10:43:41.606-07:00Chris - send me an e-mail directly pse
Chris - send me an e-mail directly pse<br /><br />Steve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-57817630750937577032015-10-21T07:18:33.922-07:002015-10-21T07:18:33.922-07:00I've completed the construction phase of a Chi...I've completed the construction phase of a Chinese 49-er. It recieves and transmits, but I've discovered when I listen on other receivers that it puts out a continual carrier between keying at the frequency of the crystals. Is this the spurious oscillation mentioned in previous comments? Where should I look for best results in fixing it? Would it be the crystal in the oscillator circuit or one of the transisters that is the most likely culprit?Chris/Janhttps://www.blogger.com/profile/01074462648241399945noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-31787796549596422192015-05-31T16:51:33.752-07:002015-05-31T16:51:33.752-07:00Graham - thank you for bringing this to my attenti...Graham - thank you for bringing this to my attention! I have made the VE3AB correction and of course thank you very much as well for your original posting and follow-up to the problem....sorry for the mixup.Steve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-84644306326947459942015-05-31T15:30:31.218-07:002015-05-31T15:30:31.218-07:00Good evening Steve,
As always, I find many inform...Good evening Steve,<br /><br />As always, I find many informative and enjoyable postings on your blog.<br /><br />However, I must point out in your post regarding the 49'er that the "copy paste" of a post on the GQRP group was in fact mine. Of that I have no issue but later on you attribute much good information to Earl Andrews VE3GTC. In fact my call is VE3GTC, Earl's is VE3AB and his web site is a veritable cornucopia of interesting stuff.<br /><br />cheers es 73, Graham ve3gtcAnonymousnoreply@blogger.com