[Elecraft] K1 Backlight Installation
I've reached the point in assembling my K1 where I install the backlight kit and have a few questions: 1. I assume that the black neoprene LCD spacer that comes with the K1 is not used when the backlight kit is installed? In other words, the only items under the LCD will be the insulator card and backlight? 2. The K1 manual directs shifting to the backlight installation instructions immediately after the installation of U1. However, one of the first steps of the backlight instructions is to remove U1. Is this step only applicable when installing the backlight on a completed K1 where the LCD has to first be removed, or is it also applicable to the backlight installation during a new build of a K1 (i.e., LCD not previously installed)? 3. Under the section "Preparation of the Backlight Installation Site," the backlight instructions direct the flush-trim of all component leads between the two rows of LCD PC board pads. Does this mean to flush-trim the U1 socket pins or does the insulator card rest on top of the untrimmed U1 socket pins? 4. The backlight instruction graphic shows the right side of the foam tape on the insulator card being completely flush with the right side of the blue backer paper. However, on my insulator card, the right side of the blue backer paper extends about 1/16 inch beyond the right side of the white foam tape. Should I trim the right side of the blue backer paper to be flush with the right side of the white foam tape? 5. Step 25 of the backlight instructions directs the testing of the backlight illumination level prior to soldering the LCD pins. Since I've yet to assemble the RF board and, therefore, can't apply power to the backlight as directed in this step, is there any other testing of the backlight that I need to do prior to soldering the LCD pins? Scott N4KTR __ 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
[Elecraft] K1 RF Board Trimmer Caps
My K1 RF board ceramic trimmer capacitors C13 and C20 have an outline shape that differs from either that described in the K1 assembly instructions or on the silkscreen outline on the RF board PCB. This is the same question that Dean asked back on 10/27/12. Don's answer described trimmer capacitors with an angular shape. This description perfectly describes the trimmer capacitors on the KFL1-4 filter board (e.g., figure 1 in KFL1-4 assembly instructions) but does not appear to describe the current crop of RF board trimmer caps. I didn't see any additional clarification associated with that thread. The K1 assembly manual (p. 28) describes C13/20 trimmer caps that "have one side that is flattened." The trimmer caps supplied with my K1 have a round profile with a square protrusion on one side of the profile, sort of like the profile of an old-style keyhole. I'm assuming that the square protrusion side of the trimmer cap equates to the flattened side of the PCB outline (i.e., square protrusion pointing to the rear of the PCB) and have installed my trimmer caps based on this assumption. Is this assumption correct? As long as I'm pounding away on the keyboard, here's one other question. The K1 "DC voltage check" procedure on p. 30 calls for a power supply voltage of 12-14 VDC. However, my trusty old late-70s-vintage Vanco regulated DC power supply has an unloaded DC voltage of 14.5 VDC as measured with a Fluke 115. I also note that the K1 specifications on p. 5 lists a required supply voltage of 8.5-15 VDC. I also suspect that once placed under load, my Vanco PS will drop to something less than 14 VDC. Is it OK to use this power supply for the DC voltage check procedure? Scott N4KTR __ 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
Re: [Elecraft] K1 RF Board Trimmer Caps
Don, These are definitely not the blue-bodied trim caps. I'm familiar with those as they are used in the KFL1-4, which I've already assembled. No confusion at all as to how to orient the blue-bodied, angular-nosed trim caps. The C13/20 trim caps I've now installed on my RF board appear to have a white, cylindrical, possibly ceramic body. There are no flat sides on the main body. Underneath the slotted adjusting screw is what appears to be a fiber washer, half brown and half white, with a small blob of what appears to be solder applied between the side of the adjusting screw and white half of the washer. One electrical connector is attached to the back side of the cylindrical body while the other electrical connector is attached to the square protrusion from the other side of the cylindrical body. The assumption I made during installation was to match the asymmetrical side (i.e., square protrusion) of the trim cap with the flat side marked on the PCB. Scott On Dec 24, 2012, at 10:34 AM, Don Wilhelm wrote: > Scott, > > I figure you have the blue bodied trimmers and not the older ceramic ones. > > Look at them carefully - one end is rounded (that will be the wider end with > rounded corners) while the 'shorter' end has angular corners and a flat > between those corners. That is the 'flat' side and should be aligned to the > flat shown in the manual. Be aware that the newer gold looking solder pads > do not accept silkscreening, so you must align them like is shown in the > manual. > > The consequence of mounting them backwards is that you will have to use an > insulated tool to adjust them. > > Does that clear up your confusion? > > 73, > Don W3FPR > > > On 12/24/2012 9:14 AM, Scott Krebs wrote: >> My K1 RF board ceramic trimmer capacitors C13 and C20 have an outline shape >> that differs from either that described in the K1 assembly instructions or >> on the silkscreen outline on the RF board PCB. This is the same question >> that Dean asked back on 10/27/12. Don's answer described trimmer capacitors >> with an angular shape. This description perfectly describes the trimmer >> capacitors on the KFL1-4 filter board (e.g., figure 1 in KFL1-4 assembly >> instructions) but does not appear to describe the current crop of RF board >> trimmer caps. I didn't see any additional clarification associated with that >> thread. >> >> The K1 assembly manual (p. 28) describes C13/20 trimmer caps that "have one >> side that is flattened." The trimmer caps supplied with my K1 have a round >> profile with a square protrusion on one side of the profile, sort of like >> the profile of an old-style keyhole. I'm assuming that the square protrusion >> side of the trimmer cap equates to the flattened side of the PCB outline >> (i.e., square protrusion pointing to the rear of the PCB) and have installed >> my trimmer caps based on this assumption. Is this assumption correct? >> >> As long as I'm pounding away on the keyboard, here's one other question. The >> K1 "DC voltage check" procedure on p. 30 calls for a power supply voltage of >> 12-14 VDC. However, my trusty old late-70s-vintage Vanco regulated DC power >> supply has an unloaded DC voltage of 14.5 VDC as measured with a Fluke 115. >> I also note that the K1 specifications on p. 5 lists a required supply >> voltage of 8.5-15 VDC. I also suspect that once placed under load, my Vanco >> PS will drop to something less than 14 VDC. Is it OK to use this power >> supply for the DC voltage check procedure? >> >> Scott >> N4KTR >> >> >> __ >> 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 >> > __ 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