Re: [Drakelist] 8 pole filter
GM Neil: Generally speaking, the more poles in the filter, the more it will resemble a "Perfect" filter...that is the response is 100% right up to the edge of the filter passband, then 0 past the edge of the passband. This is never achieved in real-world analog filters. The cut-off edge has a particular slope to it. So..it might be 100% inside the "edge" and drops to 50% output at some distance out from the edge. Filter shape factor is used to describe the effect of the shape on the response. Most analog filters have the passband specified at a point 3dB down the edge..or what is the bandwidth at the three dB point. It is also important to then look at what the bandwidth is at the 60 dB point as well. What this means in the real world of listening is how effectively signals outside the passband of the filter are heard. In this case, the 8 pole filter is more effective at reducing those out-of-passband signals so they will be heard even less than with a 4 pole filter. For some purposes, a "softer" filter edge is easier to listen to. Many other factors come into play as well but this is the general idea. DSP impllemented filters can have VERY sharp cut-off edges because they aren't physically adddng sections to a filter. They can approach the brickwall ideal shape in some cases. Hope this helps some. Curt KU8L Neil M Califano wrote: Why is an 8 pole 5 khz filter better than a 4 pole, since they're both 5 khz? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] My plates are shorted, and I can't tune up
Hearing the plates shorting is your first clue - another way to find the points at which they DO short, is with an ohmmeter (analog is best). Aluminum plates of caps, in some climates, develop something akin to "tin pest" in that metal. Aluminum oxides begin to "grow" on the plates; they can and will short out. Old fashioned contact-burnishers (for relays) work swell for getting rid of them, but in severe cases, you'll have to use sandpaper. Remember, the oxide IS kind a semi-conductor, so be sure to get all the remains OUT. Tom - WØEAJ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Thanks
If you plan ahead you can make the originals fit. I have mine inside my TR7 with the kit's electrolytic caps from Cumbria Designs. That said, it will be SO MUCH EASIER if you build/replace the 6 with tantalum caps. The plug connectors are another item to plan/watch for. 73, Ron WD8SBB --- On Mon, 3/7/11, pony...@aol.com wrote: From: pony...@aol.com Subject: Re: [Drakelist] Thanks To: drakelist@zerobeat.net Date: Monday, March 7, 2011, 10:13 PM Hi Gang, Sorry for not responding to all the nice people that helped me with some of my Drake woes. I've been working on a UV-3 for around six months. I had to replace countless parts, one of which was due to a dumb mistake. I inadvertently shorted 12 volts to the 5 volt line. That cost me a divider board, and many, many hours of head scratching. The UV-3 now lives. Next on my agenda is the X-Lock installation in my TR-7, I had already stuffed all the electrolytic caps, and boy did I make a mess swapping them for the Tantilum Caps after finding out the hard way that there isn't room for the tall caps. Yikes!!! Again, thanks for all the help Enjoy those Drakes.. Tom Maguire, WD8JPP -Inline Attachment Follows- ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Station upgrade?
The weather and old age have taken its toll on my old AV5 Cushcraft 5 band vertical antenna. I am considering a purchase of another all band MBVE-1UP 45 foot vertical by DX Engineering. Because I have been out of amateur radio for many years the technical knowledge that I thought knew about antennas and such has evolved so much by the various equipment manufactures that my knowledge base has become outdated somewhat. I need to stick with a vertical because of lack real estate and living in a city lot! I would like some suggestions from you who have been keeping up on the art and technology to offer some suggestions on using an antenna like the above mentioned MBVE-1, with my Drake MN2700 antenna tuner. I would like to use all of the capacity of this antenna; I also understand that the capacity of the MN2700 is limited to the standard amateur radio frequencies. I would like to use the WARC bands that I now have the capacity to use with my TR7 along with the L4B amp just recently rebuilt. It works even better now with a new power supply. Should I look for another tuner to use or purchase another MN2700 and attempt to modify it? Any suggestion or ideas would be greatly appreciated Thank you in advance Michael J TrussellKA8ASN ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] 8 pole filter
On first glance it *seems* like the more poles, the better. Certainly, the skirts will be steeper and the bandwidth at the 60 DB point will be more narrow. But, there is a price to pay for this additional selectivity -- group delay. The more poles you you have in the filter the worse the group delay spec will be. So, static crashes and other impulse signals tend to get stretched out. This can lessen the quality of the listening experience. Just another thing to stay up late, worrying about. ;-) 73, -Doug, W7KF http://www.w7kf.com Curt Nixon wrote: GM Neil: Generally speaking, the more poles in the filter, the more it will resemble a "Perfect" filter... ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] 8 Pole filter
For AM listening would a 5 khz 8 pole filter be too steep? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] SPR-4 Crystals
Hello- Does anyone on the list know where I can buy ham band crystals for the SPR-4? There used to be a lot of them on eBay but I don't see them anymore (now that I need to find some!). Also, does anyone have a TA-4 trtabsceive adapter? Thanks, Byron WA5THJ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Station upgrade?
Well I'm guessing that the only thing that has changed antenna wise is it's advertising. And most of that is now not only crap, it is an out and out lie. And because the ARRL(for one) does not require truth in the advertising that they print it sorta looks like there is all this new stuff. Most notably are vertical antennas that do not require radials or even a counterpoise. I use a Butternut HF-6V with a MN2000 and have (can) tune the WARC bands with it. I know that this does not directly address your system but the theory does. If your MN2700 is anything like the older MN2000 you should not have a problem. DO NOT use RG8X. I think that anything short of Times LMR 400 is a waste of money and time. The best thing anyone can do is to ignore the advertising and get your information from other Hams... just like you are doing. Take Care KB8NXO On Tue, Mar 8, 2011 at 6:30 PM, Michael & Sue Trussell < mtruss8...@comcast.net> wrote: > The weather and old age have taken its toll on my old AV5 Cushcraft 5 band > vertical antenna. I am considering a purchase of another all band MBVE-1UP > 45 foot vertical by DX Engineering. Because I have been out of amateur radio > for many years the technical knowledge that I thought knew about antennas > and such has evolved so much by the various equipment manufactures that my > knowledge base has become outdated somewhat. I need to stick with a vertical > because of lack real estate and living in a city lot! > > > > I would like some suggestions from you who have been keeping up on the art > and technology to offer some suggestions on using an antenna like the above > mentioned MBVE-1, with my Drake MN2700 antenna tuner. I would like to use > all of the capacity of this antenna; I also understand that the capacity of > the MN2700 is limited to the standard amateur radio frequencies. I would > like to use the WARC bands that I now have the capacity to use with my TR7 > along with the L4B amp just recently rebuilt. It works even better now with > a new power supply. > > > > Should I look for another tuner to use or purchase another MN2700 and > attempt to modify it? > > > > Any suggestion or ideas would be greatly appreciated > > > > > > Thank you in advance > > > > > > Michael J TrussellKA8ASN > > ___ > Drakelist mailing list > Drakelist@zerobeat.net > http://mailman.zerobeat.net/mailman/listinfo/drakelist > > ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] (no subject)
"It depends. If there are interfering stations nearby, it would help to have a narrow filter. If clear conditions, an 8 kc filter would improve the fidelity." Do you mean an 8 pole filter or an 8 khz filter? Why would 8 pole be 8 kc? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] SPR-4 Crystals
Byron: I've purchased most of my SPR-4 crystals from International Crystal Manufacturing in Oklahoma City, OK. They're on the web: icmfg.com When you speak with the order desk, tell them the range you want to cover and that you have an SPR-4--they will know the type of crystal and the frequency you'll need. Your crystals will arrive in 2-3 weeks. I strongly recommend them! 73, Tony N3WAK ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] 8 Pole filter
"It depends. If there are interfering stations nearby, it would help to have a narrow filter. If clear conditions, an 8 kc filter would improve the fidelity." Do you mean an 8 pole filter or an 8 khz filter? Why would 8 pole be 8 kc? ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] WANTED: DRAKE R-4C
Looking for a fully functional, clean rust and pitting free chassis, high serial number [above 28500] R-4C receiver complete with the 4-NB noise blanker; MS-4 speaker; xtals for 160, 60, 30, 17,12m; original instruction manual; complete set of filters for 6kHz, 1.5kHz,.5kHz, .25kHz.Detailed info on the unit would be most welcomed and, if any modifications may have been done to the unit, detailed information on any and all modifications would be most welcomed in advance of purchase. Contact me in advance with details on unit's condition, cost price, method of shipping to a U.S. address! My thanks. Vy 73, C6ANI, Ric. ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] L4B Fan Mounting Grommets
*Anyone know where you can get the fan mounting Grommets for the L4B?* *Thanks * *Woody (KO4BG)* ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Drakelist Digest, Vol 33, Issue 12
> > I've been using a Cushcraft R-7 "half-wave" Vertical on the roof of my > house driven be my Drake gear; I've been feeding it with RG-8X with no > problem, both QRP and QRO. I'm curious why we should avoid RG-8X? What's > the big deal about the "X" cable? > BTW, the R-7 is designed to configure and operate with no radials, and is very easy to assemble, erect and tune. I also have the Butternut HF-6 which works great! but requires some work to its "mind right," adjusting the sections and the radials and the ground. can't say that one is a better performer than the other but the Cushcraft is definitely easier. Grant > Message: 7 > Date: Tue, 8 Mar 2011 20:49:18 -0500 > From: Richard Palmer > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] Station upgrade? > Message-ID: > > Content-Type: text/plain; charset="iso-8859-1" > > Well I'm guessing that the only thing that has changed antenna wise is it's > advertising. And most of that is now not only crap, it is an out and out > lie. And because the ARRL(for one) does not require truth in the > advertising > that they print it sorta looks like there is all this new stuff. Most > notably are vertical antennas that do not require radials or even a > counterpoise. > > I use a Butternut HF-6V with a MN2000 and have (can) tune the WARC bands > with it. > I know that this does not directly address your system but the theory does. > If your MN2700 is anything like the older MN2000 you should not have a > problem. DO NOT use RG8X. I think that anything short of Times LMR 400 is a > waste of money and time. > > The best thing anyone can do is to ignore the advertising and get your > information from other Hams... just like you are doing. > > Take Care > KB8NXO > > On Tue, Mar 8, 2011 at 6:30 PM, Michael & Sue Trussell < > mtruss8...@comcast.net> wrote: > > > The weather and old age have taken its toll on my old AV5 Cushcraft 5 > band > > vertical antenna. I am considering a purchase of another all band > MBVE-1UP > > 45 foot vertical by DX Engineering. Because I have been out of amateur > radio > > for many years the technical knowledge that I thought knew about antennas > > and such has evolved so much by the various equipment manufactures that > my > > knowledge base has become outdated somewhat. I need to stick with a > vertical > > because of lack real estate and living in a city lot! > > > > > End of Drakelist Digest, Vol 33, Issue 12 > * > ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist