[Drakelist] New price for L-75
My friend has decided to lower his price to $700. Any takers? Contact me via list or directly. Tom Holmes, N8ZM ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] FW: L-75 for sale
He wants me to add that he will include 15' of correct power cord cable, and the 3-prong polarized plug for 220 VAC that matches the amp. He told me that one sold recently at R&L, our local candy store, for $1000. Must have been before the economy collapsed 😊. Tom Holmes, N8ZM -Original Message----- From: Tom Holmes Sent: Saturday, April 04, 2020 5:06 PM To: 'drakelist@zerobeat.net' Subject: L-75 for sale Belongs to a friend. In pristine condition. Contact me via this list and I'll pass along his contact info. Tom Holmes, N8ZM ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] L-75 for sale
Belongs to a friend. In pristine condition. Contact me via this list and I'll pass along his contact info. Tom Holmes, N8ZM ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R4A-B Detector Amp Q5
:-). I wonder if there is an asterisk on the schematic next to some bias resistor that says hand chosen. Oh well. Have fun! Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Curt Nixon > Sent: Tuesday, February 26, 2013 12:30 PM > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] R4A-B Detector Amp Q5 > > Hi Tom: > > The collector goes to hard saturation value. Less than .2V. I did the test using a > Huntron on a few of the swaps just to be sure. > > I also carefully watched the base voltage established thru the detector diode. It > stays right around .5-.6V. Even repalced the diode to see if that might be the > case but same result. > > At this point, I guess I am going to try to find a genuine 3394 and call it a day. It > all works fine when I put in a working device from another > R4 so suspect something particular about the device. Transistors were a lot less > controlled in 1968 so it may not be close. Dont have a curve tracer and not going > to remove it again to do an Hfe test on it the hard way. > > It is just a curiosity now. I taught solid-state design and theory in Navy and later in > college and thought I had seen most issues. ;) > > Curt > KU8L > > On 2/26/2013 12:02 PM, Tom Holmes wrote: > > Well, it was worth a shot. Since I don't have the circuit in front of > > me I can't make a more educated guess. > > > > Since you caught the lead issue, I'll assume that you also did the > > diode test on the replacement parts. I have seen a few cases where the > > NTE doc's are wrong about the leads though. When the collector voltage > > goes to near zero, is it .2 V or .6 V? The first case is a saturated > > transistor; the second is a diode junction, which would suggest the pinout info is > wrong. > > > > When I get back from some errands, I'll look in my NTE book to see if > > I can find any other clues. > > > > Happy hunting! > > > > Tom Holmes, N8ZM > > Tipp City, OH > > EM79 > > > > > >> -Original Message- > >> From: drakelist-boun...@zerobeat.net > > [mailto:drakelist-boun...@zerobeat.net] > >> On Behalf Of Curt Nixon > >> Sent: Tuesday, February 26, 2013 11:43 AM > >> To: drakelist@zerobeat.net > >> Subject: Re: [Drakelist] R4A-B Detector Amp Q5 > >> > >> Hi Tom: > >> > >> Yes...there are the lead arrangement issues but I accounted for them. > >> The typical EBC Vs ECB issue. Easy in this case because they used > >> the triangular hole pattern instead of the inline pattern on both the > >> R4A and > > B version > >> modules. > >> > >> Curt > >> > >> On 2/26/2013 10:49 AM, Tom Holmes wrote: > >>> HI Curt.. > >>> > >>> It almost sounds like there is a different lead arrangement on the > >>> 3393. Any well designed circuit of that era would have had to > >>> tolerate the typical high variability of Hfe to avoid tedious hand > >>> picking of parts, although that may have been done in this case. > >>> > >>> Tom Holmes, N8ZM > >>> Tipp City, OH > >>> EM79 > >>> > >>> > >>>> -Original Message- > >>>> From: drakelist-boun...@zerobeat.net > >>> [mailto:drakelist-boun...@zerobeat.net] > >>>> On Behalf Of Curt Nixon > >>>> Sent: Tuesday, February 26, 2013 10:40 AM > >>>> To: Drake Forum > >>>> Subject: [Drakelist] R4A-B Detector Amp Q5 > >>>> > >>>> GM All: > >>>> > >>>> Has anyone else had trouble getting a general purpose sub working > >>>> in the > >>> Q5 AM > >>>> detector amp position? > >>>> > >>>> I tried several close NTE GP subs and also a 3393 which is same > >>>> parameters > >>> ex > >>>> Hfe which is slightly different. > >>>> > >>>> The transistor comes on but with the grounded emitter, pulls the > >>>> collector > >>> voltage > >>>> to near zero. As soon as I put in a "real" orignal > >>>> 3394 from a R4A, it works as it should--good fidelity and collector > >>> voltage at about > >>>> 5V from the supply rail of 10V. > >>>> > >>>> Is this design so sensitive to Hfe as to be
Re: [Drakelist] R4A-B Detector Amp Q5
Well, it was worth a shot. Since I don't have the circuit in front of me I can't make a more educated guess. Since you caught the lead issue, I'll assume that you also did the diode test on the replacement parts. I have seen a few cases where the NTE doc's are wrong about the leads though. When the collector voltage goes to near zero, is it .2 V or .6 V? The first case is a saturated transistor; the second is a diode junction, which would suggest the pinout info is wrong. When I get back from some errands, I'll look in my NTE book to see if I can find any other clues. Happy hunting! Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Curt Nixon > Sent: Tuesday, February 26, 2013 11:43 AM > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] R4A-B Detector Amp Q5 > > Hi Tom: > > Yes...there are the lead arrangement issues but I accounted for them. > The typical EBC Vs ECB issue. Easy in this case because they used the > triangular hole pattern instead of the inline pattern on both the R4A and B version > modules. > > Curt > > On 2/26/2013 10:49 AM, Tom Holmes wrote: > > HI Curt.. > > > > It almost sounds like there is a different lead arrangement on the > > 3393. Any well designed circuit of that era would have had to tolerate > > the typical high variability of Hfe to avoid tedious hand picking of > > parts, although that may have been done in this case. > > > > Tom Holmes, N8ZM > > Tipp City, OH > > EM79 > > > > > >> -Original Message- > >> From: drakelist-boun...@zerobeat.net > > [mailto:drakelist-boun...@zerobeat.net] > >> On Behalf Of Curt Nixon > >> Sent: Tuesday, February 26, 2013 10:40 AM > >> To: Drake Forum > >> Subject: [Drakelist] R4A-B Detector Amp Q5 > >> > >> GM All: > >> > >> Has anyone else had trouble getting a general purpose sub working in > >> the > > Q5 AM > >> detector amp position? > >> > >> I tried several close NTE GP subs and also a 3393 which is same > >> parameters > > ex > >> Hfe which is slightly different. > >> > >> The transistor comes on but with the grounded emitter, pulls the > >> collector > > voltage > >> to near zero. As soon as I put in a "real" orignal > >> 3394 from a R4A, it works as it should--good fidelity and collector > > voltage at about > >> 5V from the supply rail of 10V. > >> > >> Is this design so sensitive to Hfe as to be marginal or need to be > >> hand > > selected? > >> Certainly the 3393 is well within the spec range of the 3394. > >> > >> Thanks > >> > >> Curt > >> KU8L > >> > >> ___ > >> 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 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
Re: [Drakelist] R4A-B Detector Amp Q5
HI Curt.. It almost sounds like there is a different lead arrangement on the 3393. Any well designed circuit of that era would have had to tolerate the typical high variability of Hfe to avoid tedious hand picking of parts, although that may have been done in this case. Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Curt Nixon > Sent: Tuesday, February 26, 2013 10:40 AM > To: Drake Forum > Subject: [Drakelist] R4A-B Detector Amp Q5 > > GM All: > > Has anyone else had trouble getting a general purpose sub working in the Q5 AM > detector amp position? > > I tried several close NTE GP subs and also a 3393 which is same parameters ex > Hfe which is slightly different. > > The transistor comes on but with the grounded emitter, pulls the collector voltage > to near zero. As soon as I put in a "real" orignal > 3394 from a R4A, it works as it should--good fidelity and collector voltage at about > 5V from the supply rail of 10V. > > Is this design so sensitive to Hfe as to be marginal or need to be hand selected? > Certainly the 3393 is well within the spec range of the 3394. > > Thanks > > Curt > KU8L > > ___ > 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
Re: [Drakelist] T-4XB power switch
Does anyone know if the TR5 switch is common to the TR7 or other models? Mine has been bad for a long time and I have just jumpered it to get by. Tom Holmes, N8ZM Tipp City, OH EM79 From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of Charles Ring Sent: Wednesday, July 25, 2012 5:30 AM To: Bill Frost Cc: drakelist@zerobeat.net Subject: Re: [Drakelist] T-4XB power switch Thanks, I will probably leave it turned on and switch it externally. 73 de W3NU On 7/24/2012 0914, Bill Frost wrote: Hello Charles, I suspect the small spring inside the on/off switch cap got hung up after sitting idle for awhile. I would not recommend a lubricant since it is switching power. Drake stocked the on/off switch cap part of the gain control and also the on/off switch cap for the R-4B. We replaced several of these in the service department. John Kriner has the R-4B switch caps in his store on ebay, he thinks the switches are the same. But, I'm not so sure, I know they had different part numbers, but I never tried using one for the other, as we always had both parts. If interested in getting a "spare" switch cap, contact John Kriner, The Man Electronics. 73, Bill wd8dfp _ ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Me to...
Nope, 'cuz Time-Warner's Roadrunner did it to me too. Tom Holmes, N8ZM Tipp City, OH EM79 From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of sebdesnCC Sent: Thursday, March 08, 2012 12:38 PM To: drakelist@zerobeat.net Subject: [Drakelist] Me to... As someone said must be good ol' Comcast. Bud W0HG ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] R4C Sherwood mods
Adrian… I can’t resist this comment to your Jaguar/Bentley question and being fond of both vehicle lines. It seems to me you would call that car a Jentley rather than say, a Baguar. OK, that’s my last bad joke for 2011. I promise. Happy New Year to all! Tom Holmes, N8ZM Tipp City, OH EM79 From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of Adrian Sent: Saturday, December 31, 2011 6:35 AM To: John Brown Cc: drakelist@zerobeat.net Subject: Re: [Drakelist] R4C Sherwood mods A vacuum tube-born radio with loads of solid state mods ? Sorry but then isn't a vacuum made receiver,transmitter, twin line ( etc ) anymore. The FUN about those "boathanchors" is "use it as it is". If i wanna something improved...ill buy a new product. At my side, the challenging while using old stuff is fun, fun and fun. The battle against big, closed, splatters while you have to fight with the passband tuning AND rf gain...etc etc. It's like to drive a Jaguar, but with a (eg) Bentley engine inside. Do we can call that car a Jaguar ? I don't think so. So, at my side, a Drake product, with plenty of solid state things inside...isn't a Drake anymore. Obv it's only my opinion. '73 de Adrian iz3svi On Sat, 31 Dec 2011 12:06:30 +1100, "John Brown" wrote: Max, if you are inclined towards doing all of the R-4C Sherwood mods on your receiver then I would say it would be well worthwhile. The complete mods really puts the R4-C ahead of the pack. I have done 2 R4C’s this way and wouldn’t hesitate to do them again. In terms of individual mods, then the power supply is a must and perhaps the filter capacitors at the same time. The audio module gets rid of the class A audio amp which is a heat generator and source of PTO drift. I believe you would need to do the audio mod if the power supply is upgraded. So once you start you might as well keep going. Best of luck JB From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] On Behalf Of AirRadio Sent: Saturday, 31 December 2011 8:28 AM To: drakelist@zerobeat.net Subject: [Drakelist] R4C Sherwood mods I am thinking about doing the full works Sherwood mods on my R4-C. Which are the best to do? I don't mind how far I go with this, I just want the best receiver for my money, I would like it for Top band use but I know it will be good for all frequencies however 160M is where I want to go. 73 Max M0GHQ/W8BX ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] PTO/VFO
Until the advent of synthesizer IC's capable of working at 130 MHz and all electric tuning schemes, all automotive radios used PTO's, along with Permeability Tuned RF stages. There were typically three P-tuned coils per band, one for the LO, the other two the RF stages. They could easily be set up to track across the AM or FM band. The production tuning was actually done by machines in the later years when the capability became available. The other reason for the PTO was that, especially in a mobile environment, there were fewer pressure based connections (think variable capacitors and trimmers) to become corroded and noisy. Microphonics are typically lower as well, so bumpy roads would not appear to affect the radio. Another benefit was much smoother tuning than could be accomplished with a rotary capacitor, and simple mechanicals, unless you had one of the signal seeker jobs! What does this have to do with Drake's? My guess is that Drake, Collins, et all, appreciated the same benefits, as they were also interested in mobile applications. Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Richard Knoppow > Sent: Friday, February 18, 2011 9:08 PM > To: K9sqg > Cc: Drakelist@zerobeat.net > Subject: Re: [Drakelist] PTO/VFO > > > - Original Message - > From: "K9sqg" > To: ; > Cc: > Sent: Friday, February 18, 2011 3:56 PM > Subject: Re: [Drakelist] PTO/VFO > > > Typically, a PTO refers to a permeability tuned oscillator. > In other words, it tunes the inductor with a core that moves > in and out of the coil. A VFO typically refers to an > oscillator that varies a capacitor to vary the frequency. > However, VFO is sometimes used to refer to a traditional > VFO, a PTO, and even VCO. > > Collins also seems to use both terms although theirs > _is_ a PTO. I've also seen other confusing terms used, I > think Hallicrafters called theirs a LMO (Linear Master > Oscillator) or something of the sort. > The advantage of a permeability tuned oscillator is that > its fairly easy to get a linear frequency scale by shaping > the coil so that the inductance has a square-law relation to > linear movment of the core. Its possible to shape the plates > of a variable air capacitor to achieve the same thing but > the plates become extreme in shape and are hard to make. > Such "straight-line-frequency" capacitors were offered by > Cardwell and Hammarlund, maybe also National, in the early > 1930's but I think they proved to cause more problems than > they solved. > There have also been oscillators with simultaneous > variation of inductance and capacitance, mostly for VHF/UHF > applications. This has the advantage of more linear dial > calibration and probably also higher Q. General Radio used > this in one or more of its instruments and I think had a > patent on it. > A problem with the PTO is that its difficult to get the > coils to be exactly square-law so some means of correcting > them is needed if the dial calibration is to be accurate > without individual calibration. Collins used a "corrector > stack" consisting of a series of thin washers clamped by a > bolt. The washers could be slid to make a cam surface > according to the correction needed. The surface was followed > by a roller attached to a lever which could move the > position of the nut driving the core just a little. the > result was that the exact frequency could be adjusted > continuously along the working length of the coil. Other > manufacturers made similar arrangements that accomplished > the same end without infringing on the Collins patent. I > don't think Drake uses any such arrangement. > > > -- > Richard Knoppow > Los Angeles > WB6KBL > dickb...@ix.netcom.com > > > ___ > 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
Re: [Drakelist] PROBLEM FOUND ---OT Help on RF interference (New QTH)
Hi Lee... Congrats on finding the problem! Franklin Electric ought to be responsive to the problem, especially if you remind them that the FCC takes a dim view of such things from un-intentional radiators. And since it is a new installation, there might even be some warranty recourse for you. It wouldn't hurt your case to be able to show that it also interferes with your AM radios, or other household receivers. Even if you don't regularly listen to AM. If they do not cooperate, at least try to shame them into giving you a good schematic of the device. From there, it should be possible to figure out a suitable scheme to clean up the noise. Having the dipole in the house probably made the problem more noticeable. When you can transition to an outside antenna, things might improve quite a lot. Notice I said might. Have fun and happy holidays! Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of kc9...@aol.com > Sent: Wednesday, December 22, 2010 12:36 AM > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] PROBLEM FOUND ---OT Help on RF interference (New > QTH) > > Frst of all...thanks very much to moderators for allowing us to work on > this...my KWM-2,and C line both are going nuts on this noisesolid > S-9! > The TT Orion II with the noise blanker is only slightly better > hopefully more than just me have been helped by all the excellant > advice! > > I have found the problem.it is in fact here in my house! (Thanks > God!) > It is the Control box for the Constant Pressure Well' > It is 230 VAC, single phase...but it make 3 Phase power for the well! > It is made by Franklin Electric. > This is a new house and it was part of the new construction... > > SO, why did I not find it when I turned everything off. > I Have a Geo furnace that uses well water (open system) so when the > furnace runs so does the well pump. > Last night I was looking for this problemand I noticed the noise > WAS preset even when the furnace was NOT running. So I did not shut off > the wellBUT now I know that my wife was doing laundry last night! > So, I was not thorough enough in my turning off loads. I skipped the > one that was the culprit. > > Now the hard part..I sure do need my heat...so I will have to call > Franklin Electric tomorrow and try to get help on thisf they do not > have an answer or jut say tough cookies..what to do??? > > THANKS to everyone that provided suggestions they were all good and I > have them saved for any future issues. > > 73, > Lee, KC9CDT > > > > Lee Simmonds > Summit DCS > > 260-799-4077 Office > 260-403-6936 Cell > > > -Original Message- > From: Bob Marchese > To: drakelist ; kc9cdt > Sent: Tue, Dec 21, 2010 9:35 pm > Subject: Re: [Drakelist] OT Help on RF interference (New QTH) > > > Hi Lee, > > You mentioned, "tonight about every 10-15 minutes". Does this only > occur at > night? If so and you have any street lamps containing HPS (High > Pressure > Lamps) cycling that could be a possibility to check out. > > Bob, K1NOK > > > > - Original Message - > From: > To: > Sent: Tuesday, December 21, 2010 8:36 PM > Subject: [Drakelist] OT Help on RF interference (New QTH) > > > > Darn new QTH...I am finding a BIG problem, here. > > I have a pulsing RF noise about every 40-50 KC. If it were audio I > would > > describe it as the sound of an old pump, (maybe 10 times a second) > or > > something. It does top and go...tonight about every 10-15 minutes or > > so...ot exactly though. It's winter here. > > > > > > The signal is about 20 KC wide and repeats ever 50 KC. > > starts at 80 mtrs goes all the way to 10. > > > > Any ideas, or is there a better list to go to for help on this. > > Yes, I have turned off evey breaker in my house in sequence...it > ain't > > here. > > > > Closest neighbor is about 250 ft. > > I'm at a small lake out in the country with maybe 180 houses around > > it...only 30% here this time of year. > > > > 73, > > Lee > > > > > > > > > > ___ > > 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 mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] OT Help on RF interference (New QTH)
Hi Lee... Could be a lot of things, from an electric fence to a gas furnace igniter. First thing to try is to see if you can pin down a direction, say with a loop type antenna. If you have a portable AM/FM radio, you might see if you can hear it at the top of the AM band, and use the directional loopstick antenna in that to give you a direction. Then triangulate on it. I am guessing that you are hearing it on an outside dipole or beam. See if you can hear it on a short wire in your shack as well. That will give you a clue as to how close it is to your QTH. If you are using a beam, does rotating it change the signal strength? Given the fact that it has an on/off cycle, it could well be someone's furnace with some kind of PWM control on the blower. Unfortunately, there are lots of possibilities, and it may take a bit of detective work to locate the source, and a lot of diplomacy to get it stopped. Keep us posted. Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of kc9...@aol.com > Sent: Tuesday, December 21, 2010 8:36 PM > To: drakelist@zerobeat.net > Subject: [Drakelist] OT Help on RF interference (New QTH) > > Darn new QTH...I am finding a BIG problem, here. > I have a pulsing RF noise about every 40-50 KC. If it were audio I > would describe it as the sound of an old pump, (maybe 10 times a > second) or something. It does top and go...tonight about every 10-15 > minutes or so...ot exactly though. It's winter here. > > > The signal is about 20 KC wide and repeats ever 50 KC. > starts at 80 mtrs goes all the way to 10. > > Any ideas, or is there a better list to go to for help on this. > Yes, I have turned off evey breaker in my house in sequence...it ain't > here. > > Closest neighbor is about 250 ft. > I'm at a small lake out in the country with maybe 180 houses around > it...only 30% here this time of year. > > 73, > Lee > > > > > ___ > 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
Re: [Drakelist] T-4X fan mod
HI Dick... Well, having more voltage to the fan can't hurt. Seems ironic that the fan slows down just when you need it most ;-). Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: Dick KF4NS [mailto:kf4nsra...@verizon.net] > Sent: Wednesday, October 27, 2010 4:15 PM > To: Tom Holmes; drakelist@zerobeat.net > Subject: Re: [Drakelist] T-4X fan mod > > OH BUGGERS ! > > Tom, you are absolutely right. I know very little about fans and their > design. Never gave it a thought. It is a brushless. Oh well, I will > give the full wave multiplier a try anyway since I already received > the parts. > Probably will end up with more NEW spare parts. > > Thanks for the enlightening. > > 73, Dick KF4NS > St Petersburg, FL 33714 USA > Keep The Glow! > > - Original Message - > From: "Tom Holmes" > To: "'Dick KF4NS'" ; > Sent: Wednesday, October 27, 2010 10:16 AM > Subject: RE: [Drakelist] T-4X fan mod > > > > Hi Dick... > > > > I am guessing that your 24 Volt fan has a solid state commutation > > circuit > > (i.e., brushless). The slowdown is most likely due to RF goofing up > > the > > switching circuitry, not voltage drop on transmit. > > > > Tom Holmes, N8ZM > > Tipp City, OH > > EM79 > > > > > >> -Original Message- > >> From: drakelist-boun...@zerobeat.net > > [mailto:drakelist-boun...@zerobeat.net] > >> On Behalf Of Dick KF4NS > >> Sent: Tuesday, October 26, 2010 7:08 PM > >> To: drakelist@zerobeat.net > >> Subject: Re: [Drakelist] T-4X fan mod > >> > >> Paul and all, > >> I have had a 24vdc .06A fan on the back of my TR4C cage for some > >> time, > >> running off of a diode and 1000mfd cap tapped off the 12vac supply > >> just outside the cage. I just noticed recently that the fan really > >> slows down during full power xmit. > >> > >> I am now modifying it to be a voltage doubler with 2 4003's and two > >> 22mfd 100vdc caps. I am hoping this solves the problem. Will let > >> you > >> know how it works. When I used a 12vdc fan it was too noisy but > >> slowing it down with a resistor did not help until it was running > >> too > >> slow to do any good. The 24v runs much quieter and draws less > >> current. > >> > >> 73, Dick KF4NS > >> St Petersburg, FL 33714 USA > >> Keep The Glow! > >> > >> - Original Message - > >> From: > >> To: > >> Sent: Monday, October 25, 2010 9:53 PM > >> > -- > >> > > >> > Message: 6 > >> > Date: Mon, 25 Oct 2010 21:52:44 EDT > >> > From: ph...@aol.com > >> > To: drakelist@zerobeat.net > >> > Subject: [Drakelist] T-4X fan mod > >> > Message-ID: <46ac0.5f81cd0b.39f78...@aol.com> > >> > Content-Type: text/plain; charset="us-ascii" > >> > > >> > I found two articles on adding a fan to a T-4X. The first one > >> > uses > >> > only a > >> > diode & capacitor and uses the size of the capacitor to control > >> > the > >> > amplitude of the half-wave rectified DC voltage. The fan is > >> > configured to draw > >> > air OUT of the PA enclosure. > >> > > >> > > _http://www.wb4hfn.com/DRAKE/DrakeArticles/TechTips/TransmitterFan.htm_ > >> > (http://www.wb4hfn.com/DRAKE/DrakeArticles/TechTips/TransmitterFan.htm) > >> > > >> >The second article uses a dropping resistor to control the > >> > fan > >> > speed, > >> > and the fan is configured to blow air INTO the PA enclosure. > >> > > >> > _http://www.k5dkz.com/t4xfan.html_ > >> > (http://www.k5dkz.com/t4xfan.html) > >> > > >> > > >> >Circuit differences aside, any thoughts on blowing air in as > >> > opposed > >> > to sucking it out? (Yes, I know the former may get the PA cage > >> > dirtier > >> > faster). > >> > > >> >Paul, K4MSG > >> > -- next part -- > >> > An HTML attachment was scrubbed... > >> > URL: > >> > > >> > > <http://mailman.zerobeat.net/pipermail/drakelist/attachments/20101025/b0b55b > > 04/ > >> attachment.html> > >> > >> > Drakelist mailing list > >> > Drakelist@zerobeat.net > >> > http://mailman.zerobeat.net/mailman/listinfo/drakelist > >> > > >> > > >> > End of Drakelist Digest, Vol 28, Issue 37 > >> > * > >> > >> > >> ___ > >> 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
Re: [Drakelist] T-4X fan mod
Hi Dick... I am guessing that your 24 Volt fan has a solid state commutation circuit (i.e., brushless). The slowdown is most likely due to RF goofing up the switching circuitry, not voltage drop on transmit. Tom Holmes, N8ZM Tipp City, OH EM79 > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Dick KF4NS > Sent: Tuesday, October 26, 2010 7:08 PM > To: drakelist@zerobeat.net > Subject: Re: [Drakelist] T-4X fan mod > > Paul and all, > I have had a 24vdc .06A fan on the back of my TR4C cage for some time, > running off of a diode and 1000mfd cap tapped off the 12vac supply > just outside the cage. I just noticed recently that the fan really > slows down during full power xmit. > > I am now modifying it to be a voltage doubler with 2 4003's and two > 22mfd 100vdc caps. I am hoping this solves the problem. Will let you > know how it works. When I used a 12vdc fan it was too noisy but > slowing it down with a resistor did not help until it was running too > slow to do any good. The 24v runs much quieter and draws less > current. > > 73, Dick KF4NS > St Petersburg, FL 33714 USA > Keep The Glow! > > - Original Message - > From: > To: > Sent: Monday, October 25, 2010 9:53 PM > > -- > > > > Message: 6 > > Date: Mon, 25 Oct 2010 21:52:44 EDT > > From: ph...@aol.com > > To: drakelist@zerobeat.net > > Subject: [Drakelist] T-4X fan mod > > Message-ID: <46ac0.5f81cd0b.39f78...@aol.com> > > Content-Type: text/plain; charset="us-ascii" > > > > I found two articles on adding a fan to a T-4X. The first one uses > > only a > > diode & capacitor and uses the size of the capacitor to control the > > amplitude of the half-wave rectified DC voltage. The fan is > > configured to draw > > air OUT of the PA enclosure. > > > > _http://www.wb4hfn.com/DRAKE/DrakeArticles/TechTips/TransmitterFan.htm_ > > (http://www.wb4hfn.com/DRAKE/DrakeArticles/TechTips/TransmitterFan.htm) > > > >The second article uses a dropping resistor to control the fan > > speed, > > and the fan is configured to blow air INTO the PA enclosure. > > > > _http://www.k5dkz.com/t4xfan.html_ > > (http://www.k5dkz.com/t4xfan.html) > > > > > >Circuit differences aside, any thoughts on blowing air in as > > opposed > > to sucking it out? (Yes, I know the former may get the PA cage > > dirtier > > faster). > > > >Paul, K4MSG > > -- next part -- > > An HTML attachment was scrubbed... > > URL: > > > <http://mailman.zerobeat.net/pipermail/drakelist/attachments/20101025/b0b55b 04/ > attachment.html> > > > Drakelist mailing list > > Drakelist@zerobeat.net > > http://mailman.zerobeat.net/mailman/listinfo/drakelist > > > > > > End of Drakelist Digest, Vol 28, Issue 37 > > * > > > ___ > 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
Re: [Drakelist] UV-3 knobs
Hi Nigel... Yes, they are for 1/4" shafts, with set screws. As best we can determine, these are smaller and / or a different style from other Drake ham rig knobs. The W-4 wattmeter uses the same style, but larger, for example. As best we can tell, these are unique to the UV-3 as far as Drake using them on ham rigs. They were not available at any of the usual distributors that Jim Wagner and I checked, so we went straight to a manufacturer. He has a small qty in stock, but has a fairly high minimum order, so if we can find enough interest, everybody wins. No profit or getting ours for free in this deal; we will pay the same as everyone else for the ones we buy. Bulk buy simply lowers everyone's cost. We would like to know fairly soon if folks are interested so we can follow up with the supplier. If there is a lot of interest, we might be able to negotiate an even better price. And we are willing to sell them in smaller quantities than the complete radio set of 8, but consider that orders for just one or two may cost more for postage than the cost of the knobs. We will do what we can to keep that under control, the biggest cost may be a bubble wrap type envelop to protect them from Uncle Sam's delivery service. Tom Holmes, N8ZM > -Original Message- > From: drakelist-boun...@zerobeat.net [mailto:drakelist-boun...@zerobeat.net] > On Behalf Of Nigel Gunn G8IFF/W8IFF > Sent: Wednesday, August 18, 2010 12:35 PM > To: Jim Wagner > Cc: drakelist@zerobeat.net > Subject: Re: [Drakelist] UV-3 knobs > > Yea. They're quite noce knobs touse on other projects provided they are for 1/4" > shafts. > > On 18-Aug-10 15:50, Jim Wagner wrote: > > We have an opportunity to buy a quantity of UV3 knobs, but there is a minimum > buy from the supplier. If there is enough > > interest, we can get them for around $24 plus postage for a set of 8. Any > interest? > > Let me know at bjwag...@bresnan.net <mailto:bjwag...@bresnan.net>. > > > > > > > > ___ > > Drakelist mailing list > > Drakelist@zerobeat.net > > http://mailman.zerobeat.net/mailman/listinfo/drakelist > > > > > > > > > > No virus found in this incoming message. > > Checked by AVG - www.avg.com > > Version: 9.0.851 / Virus Database: 271.1.1/3078 - Release Date: 08/17/10 > 18:35:00 > > > > -- > Nigel A. Gunn, 1865 El Camino Drive, Xenia, OH 45385-1115, USA. tel +1 937 > 825 5032 > Amateur Radio G8IFF W8IFF (was KC8NHF 9H3GN), e-mail ni...@ngunn.net > www http://www.ngunn.net > Member of ARRL, GQRP #11396, QRPARCI #11644, SOC #548, Flying Pigs > QRP Club International #385, > Dayton ARA #2128, AMSAT-NA LM-1691, AMSAT-UK 0182, MKARS, > ALC, GCARES, XWARN, EAA382. > > > ___ > 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] UV3 Parts request
A friend passed along to me that Terry, N7BDL, was looking for UV3 parts. There was no direct contact information, so I am pinging this list. I have the meter, and may have the black plastic piece that he wants. You can contact me via this list...I just became a subscriber! Regards, Tom Holmes, N8ZM Tipp City, OH EM79xx ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
