Re: [Elecraft] PA Transistors Maintenance in K2
Single best tip I've learned all year from this reflector. And there were many good ones. Eric KE6US On 10/29/2017 4:24 AM, Drew AF2Z wrote: > Also, you can search the pdf schematics- very convenient when tracing > through circuits spanning multiple sheets. > > 73, > Drew > AF2Z __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
When writing and validating the kit assembly procedures, I restrict myself only to the basic hand tools recommended by the design engineers. The objective is to avoid customers having to go out and buy additional tools that are not really needed. If I find that I cannot do a particular step with those tools I bring it up to Wayne and the other engineers who decide on an alternative. Sometimes that is to require a new tool. For example, we went through that over adding the requirement for a temperature-controlled, ESD-safe soldering iron some years back. The K2 and other early kits had no such requirement but as more sensitive components were used, Wayne specified that we add it to the tools requirement. On the other hand, there are times we have specifically said NOT to use a special tool. A while back we had a lot of damaged parts because builders were using electric screwdrivers that had no torque control or which had the torque set too high, so Wayne had me say NOT to use them, preferring hand pressure instead. Actually we do provide torque spec's in one case; the mounting nut for the transformer in the KPA500. That nut must work against a Belleville washer that acts as a spring. The objective is to apply the right pressure to the washer (55 inch pounds) without permanently deforming it. But, even in that case, the engineers came up with a workable alternative to avoid builders having to go out and buy a torque wrench. 73, Ron AC7AC -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of David Woolley Sent: Sunday, October 29, 2017 6:04 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] PA Transistors Maintenance in K2 As far as I can tell, no torque settings are given for any of the fasteners, wouldn't it be an idea to provide those, for people who do have suitable tools. Generally there are just warnings not to over-tighten. On 28/10/17 20:24, Mel Farrer wrote: > If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. -- David Woolley K2 06123 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
It is possible that an explicit torque has never been calculated. It is not a particularly hard thing to do however. I do not have a K2, so I can't do it, but here's the idea: 1) Fastener size/type, material, thread spec: (e.g. 4-40 x ___ pan head, phillips, zinc coated, non-rated steel 2) What does fastener anchor in? (e.g. aluminum heat sink, what alloy aluminum, thickness of threaded area. 3) Thread spec... not JUST the #4, 40 tpi, but the rating for thread engagement. 4) Check the specs for the RF transistor package, et al. Docs may/should have a max torque spec for the package maybe... package material, etc. 5) # of fasteners... usually 1 maybe 2. There are tables that specify general torque specs for fasteners, threads in various materials, etc The idea is to take the lowest max value from the list. This becomes the MAX NTE. Then, use some analysis and judgement in what forces are to be imparted to the joint static tension, sheer, axial, radial, vibration, et al... Then in this instance consider the qualities of the mating surfaces are the flat? What is the run out? Are they smooth? To what grit spec are they smooth? There's a difference between flat and smooth. What is the interface material being used? Thermal pad? Insulating? Non-insulating? Initial thickness? Read the spec sheet for the thermal pad/compound. I suspect here that the RF package has an insulating thermal pad between it and the heatsink... It was probably spec'd to keep the RF package within its operating envelope under 90% of expected operating conditions... knowing Elecraft, probably even a higher spec, and maybe a little extra to cover the "cheater". Thermal pads and MANY top quality thermal compounds REQUIRE a curing period. If the package is held with a tension spring/fastener, there is usually no requirement/need to re-torque. IF it is JUST a screw and maybe a locknut, you NEED TO RETORQUE after a given number of thermal cycles The thermal interface material flows under heat and cools when not in use. Eventually it reaches an equilibrium. You torque the fastener JUST enough to hold the junction static at this point. I'm a freak, I would use a thermally conducting thread locking/anti-seize compound (I made one). I NEVER torque unlubricated fasteners ESPECIALLY steel to aluminum interfaces. The final torque for this application is likely in the relatively low inch-pound range just guessing. I have 2 inch-pound wrenches... 0-15, and 0-70. Most people don't Key... do NOT over-torque. Consider the lever length and force applied... 73, Clay, KY5G On 10/29/2017 8:03 AM, David Woolley wrote: As far as I can tell, no torque settings are given for any of the fasteners, wouldn't it be an idea to provide those, for people who do have suitable tools. Generally there are just warnings not to over-tighten. On 28/10/17 20:24, Mel Farrer wrote: If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. -- David Woolley K2 06123 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
As far as I can tell, no torque settings are given for any of the fasteners, wouldn't it be an idea to provide those, for people who do have suitable tools. Generally there are just warnings not to over-tighten. On 28/10/17 20:24, Mel Farrer wrote: If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. -- David Woolley K2 06123 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Also, you can search the pdf schematics- very convenient when tracing through circuits spanning multiple sheets. 73, Drew AF2Z On 10/28/17 15:08, Cameron Francey wrote: A nice tip which I use when looking for anything in any sort of .pdf manual, Elecraft included as I have accumulated quite a number of them over time is to use the search feature on the .pdf reader. Ctrl+f on WIndows and cmd+f on Mac and type what I'm looking for. The index and contents tables are good, but obviously can't have everything in them, so I use the find feature a lot. Hope this helps. Regards, Cameron - AF7DK/GM7LQR From: elecraft-boun...@mailman.qth.net on behalf of Dauer, Edward Sent: Friday, October 27, 2017 8:15 PM To: elecraft@mailman.qth.net Subject: [Elecraft] PA Transistors Maintenance in K2 I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? Thanks, Ted, KN1CBR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to cameronfranceyut...@hotmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to pu...@af2z.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
The .pdf reader search function is an excellent way to find where the off-sheet connections go when reading the Elecraft schematics. 73 Bill AE6JV On 10/28/17 at 12:08 PM, cameronfranceyut...@hotmail.com (Cameron Francey) wrote: A nice tip which I use when looking for anything in any sort of .pdf manual, Elecraft included as I have accumulated quite a number of them over time is to use the search feature on the .pdf reader. Ctrl+f on WIndows and cmd+f on Mac and type what I'm looking for. The index and contents tables are good, but obviously can't have everything in them, so I use the find feature a lot. - Bill Frantz| When it comes to the world | Periwinkle (408)356-8506 | around us, is there any choice | 16345 Englewood Ave www.pwpconsult.com | but to explore? - Lisa Randall | Los Gatos, CA 95032 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Ed, I was speaking of the KPA100 amp for the K2. I don't think the KXPA100 needs any maintenance. 73, Don W3FPR On 10/28/2017 7:52 PM, Edward R Cole wrote: Don, I ran my KXPA100 mobile for 5,000 miles to-Seattle and back to AK this spring. Is there any advise for maint for extended mobile use? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Don,
I ran my KXPA100 mobile for 5,000 miles to-Seattle and back to AK
this spring. Is there any advise for maint for extended mobile use?
73, Ed - KL7UW.
making 9,600 mile R/T summer of 2018.
From: Don Wilhelm
To: "Dauer, Edward" ,"elecraft@mailman.qth.net"
Subject: Re: [Elecraft] PA Transistors Maintenance in K2
Message-ID:
Content-Type: text/plain; charset=utf-8; format=flowed
Ted,
Not Q7 and Q8 in the base K2, but for the KPA100, yes tightening the
screws for Q1 and Q2 should be done after 5 to 10 hours of operation at
greater then 50 watts.
73,
Don W3FPR
73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
dubus...@gmail.com
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Re: [Elecraft] PA Transistors Maintenance in K2
The K2 is a kit built by the customer, not Elecraft. With respect, my experience is different from Mel's. In many years working electronics field and shop service industry have found that re-tightening hardware subjected to thermal stress is commonly required by manufacturers. Manufacturers routinely do that after a "burn in" period of testing before the unit leaves the factory. Elecraft customers are instructed to do it on some gear after a period of use. The rarity of failures in spite of many thousands of rigs in service suggests that Elecraft's recommendations are good ones. BTW, when Elecraft has found that a better than metal-to-metal thermal conduction is needed, they use thermal pads instead of thermal compounds. The pads are entirely adequate and avoid customers handling messy compounds. In commercial work, when a manufacturer specifies using a thermal compound, I use GC Type 44. It is a non-silicon based compound and so does not 'migrate' from where it was placed. My small tube has plenty left and it predates the computer "age" - bought it sometime in the 1970's. Like the old Wildroot Cream Oil for hair they mean it when they say a "little dab will do ya" yet it remains flexible and never hardens. 73 Ron AC7AC -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Mel Farrer via Elecraft Sent: Saturday, October 28, 2017 12:24 PM To: Cameron Francey; Dauer, Edward; elecraft@mailman.qth.net Subject: Re: [Elecraft] PA Transistors Maintenance in K2 Ted, If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. I have been in the industry for a LONG time . Three things to remember in the mounting of any RF or high power device. Flat surfaces, minimual mating gu, and required torque. Lack of any of these will kill a device if not correct. I have never required retorqueing parts, with one exception. In 000 copper wire terminals, the copper does relax and needs to be retorqued to achieve a gas tight seal connection, but that is in industrial application. Small RF devices only need the initial torque to be correct. Mel, K6KBE __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
K2s are not factory assembled. 73, Ross N4RP On 10/28/2017 03:24 PM, Mel Farrer via Elecraft wrote: Ted, If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. I have been in the industry for a LONG time . Three things to remember in the mounting of any RF or high power device. Flat surfaces, minimual mating gu, and required torque. Lack of any of these will kill a device if not correct. I have never required retorqueing parts, with one exception. In 000 copper wire terminals, the copper does relax and needs to be retorqued to achieve a gas tight seal connection, but that is in industrial application. Small RF devices only need the initial torque to be correct. Mel, K6KBE From: Cameron Francey To: "Dauer, Edward" ; "elecraft@mailman.qth.net" Sent: Saturday, October 28, 2017 12:10 PM Subject: Re: [Elecraft] PA Transistors Maintenance in K2 A nice tip which I use when looking for anything in any sort of .pdf manual, Elecraft included as I have accumulated quite a number of them over time is to use the search feature on the .pdf reader. Ctrl+f on WIndows and cmd+f on Mac and type what I'm looking for. The index and contents tables are good, but obviously can't have everything in them, so I use the find feature a lot. Hope this helps. Regards, Cameron - AF7DK/GM7LQR From: elecraft-boun...@mailman.qth.net on behalf of Dauer, Edward Sent: Friday, October 27, 2017 8:15 PM To: elecraft@mailman.qth.net Subject: [Elecraft] PA Transistors Maintenance in K2 I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? Thanks, Ted, KN1CBR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to cameronfranceyut...@hotmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to farrerfo...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to n...@n4rp.com -- FCC Section 97.313(a) “At all times, an amateur station must use the minimum transmitter power necessary to carry out the desired communications.” __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Mel, That is NOT true for the KPA100 power transistors - and it is not because of initial torquing. The thermal pads take both time and heat to fully conform to the heatsink and any irregularities in the transistor surface. BTW, with the KPA100, Elecraft has "done their job" when the parts are put into the box. This is not sold as an assembled item - the builder must assemble it. I tighten those screws on every KPA100 that I service. I am amazed at the number I find loose. 73, Don W3FPR On 10/28/2017 3:24 PM, Mel Farrer via Elecraft wrote: Ted, If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. I have been in the industry for a LONG time . Three things to remember in the mounting of any RF or high power device. Flat surfaces, minimual mating gu, and required torque. Lack of any of these will kill a device if not correct. I have never required retorqueing parts, with one exception. In 000 copper wire terminals, the copper does relax and needs to be retorqued to achieve a gas tight seal connection, but that is in industrial application. Small RF devices only need the initial torque to be correct. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Ted, If the people at Elecraft have done their job and mounted the transistor properly with the correct torque on the mounting hardware procedure, no additional maintainance is required. I have been in the industry for a LONG time . Three things to remember in the mounting of any RF or high power device. Flat surfaces, minimual mating gu, and required torque. Lack of any of these will kill a device if not correct. I have never required retorqueing parts, with one exception. In 000 copper wire terminals, the copper does relax and needs to be retorqued to achieve a gas tight seal connection, but that is in industrial application. Small RF devices only need the initial torque to be correct. Mel, K6KBE From: Cameron Francey To: "Dauer, Edward" ; "elecraft@mailman.qth.net" Sent: Saturday, October 28, 2017 12:10 PM Subject: Re: [Elecraft] PA Transistors Maintenance in K2 A nice tip which I use when looking for anything in any sort of .pdf manual, Elecraft included as I have accumulated quite a number of them over time is to use the search feature on the .pdf reader. Ctrl+f on WIndows and cmd+f on Mac and type what I'm looking for. The index and contents tables are good, but obviously can't have everything in them, so I use the find feature a lot. Hope this helps. Regards, Cameron - AF7DK/GM7LQR From: elecraft-boun...@mailman.qth.net on behalf of Dauer, Edward Sent: Friday, October 27, 2017 8:15 PM To: elecraft@mailman.qth.net Subject: [Elecraft] PA Transistors Maintenance in K2 I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? Thanks, Ted, KN1CBR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to cameronfranceyut...@hotmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to farrerfo...@yahoo.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
A nice tip which I use when looking for anything in any sort of .pdf manual, Elecraft included as I have accumulated quite a number of them over time is to use the search feature on the .pdf reader. Ctrl+f on WIndows and cmd+f on Mac and type what I'm looking for. The index and contents tables are good, but obviously can't have everything in them, so I use the find feature a lot. Hope this helps. Regards, Cameron - AF7DK/GM7LQR From: elecraft-boun...@mailman.qth.net on behalf of Dauer, Edward Sent: Friday, October 27, 2017 8:15 PM To: elecraft@mailman.qth.net Subject: [Elecraft] PA Transistors Maintenance in K2 I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? Thanks, Ted, KN1CBR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to cameronfranceyut...@hotmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
Ted, Not Q7 and Q8 in the base K2, but for the KPA100, yes tightening the screws for Q1 and Q2 should be done after 5 to 10 hours of operation at greater then 50 watts. 73, Don W3FPR On 10/27/2017 11:15 PM, Dauer, Edward wrote: I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] PA Transistors Maintenance in K2
On page 51 of the Rev 2 KPA100 manual, I found the following: -- IMPORTANT: The hardware holding the RF power transistors in place will loosen slightly during initial use. After 5-10 hours of normal operation at 50 watts or more, remove the KPA100 assembly and its shield, then re-tighten the mounting hardware for Q1/Q2 approximately 1/8 turn. --- I didn't look to see if this was in other versions of the manual; this was the first place I looked. 73, Victor, 4X6GP Rehovot, Israel Formerly K2VCO http://www.qsl.net/k2vco/ On 28 Oct 2017 06:15, Dauer, Edward wrote: I vaguely remember reading somewhere that after some number of hours of operation – maybe 50 – the hardware holding Q7 and Q8 onto the heat sink should be tightened, I presume to maintain good heat conduction from the tabs to the sink. But I can’t find that instruction in the manual now. Anyone know where I might have gotten that notion, or did I just make it up? Thanks, Ted, KN1CBR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
