++++++++++++++++++ Date: Fri, 04 Jan 2002 10:26:58 -0600 To: "Ed Lambert" , elecraft at mailman.qth.net From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] K2 Assembly Question Ed: >Page 48 of the manual. > >"1SV149 diodes...may have a center lead that has been cut flush with the >body". > >The 1SV149 diodes supplied with my kit have center leads that protrude from >the body anywhere between 0.4 and 0.6 mm, making it impossible for them to >be installed perfectly flush with the circuit board. Do I need to find a way >to cut these leads perfectly flush or does the 0.4 to 0.6 mm not matter in >the performance of the radio? Not the first time this has been asked... needs to be repeaster periodically, just do others will know as well. Mount the device as close as practicable to the PC board. There's darn little 'empty' space between the two pads for these diodes, so, to ensure that you don't short the clipped center lead to either of the pads, I'd suggest that you mount them just slightly above the PC board... remember, 'slight'y above' means just so they won't touch the board... they do NOT have to be perfectly flush, though they'd look better that way, it won't change their operation. 73 - Tom N0SS ++++++++++++++++++ From: "Don Wilhelm" To: "Jonathan Taylor, K1RFD" , Subject: Re: [Elecraft] Another K2 Capacitor Question.... Date: Sun, 6 Jan 2002 09:38:21 -0500 Jonathan, The ARRL Handbook has a digital capacitance meter adapter that is rather easy to build - use a DVM to display the values (yes, you can use a regular DMM). Sorry, but I don't recall the section - you will have to use the index to find it. I have built both the capacitance meter and the inductance meter and can say that they work FB. Mine is in a single box with a dedicated DVM but that takes a many pole switch to switch from capacitance to inductance - the easier way is to build 2 separate adapters. 73, Don W3FPR Don Wilhelm - Wake Forest, NC W3FPR home page: http://www.qsl.net/w3fpr/ QRP-L # 485 K2 SN 0020 mailto: w3fpr at arrl.net ----- Original Message ----- From: "Jonathan Taylor, K1RFD" > All of this discussion makes me think it would be great to have a > capacitance meter on the bench, yet this is something most hams probably > don't have. > > Has anyone seen a simple circuit which would allow capacitor values to be > checked using, say, a signal source, an RF probe, and a DMM? In other > words, a "capacitance probe"? ++++++++++++++++++ Date: Sun, 06 Jan 2002 08:49:27 +0000 From: Paul Hendershott To: "Jonathan Taylor, K1RFD" CC: elecraft at mailman.qth.net Subject: Re: [Elecraft] Another K2 Capacitor Question.... I picked up an "L/C Meter IIB" from "Almost All Digital Electronics" for around $99 before I started on my K2. It cleared up a lot of confusion I had between the difficult to read parts. I found it to be extremely accurate. The great thing is that it comes in a "kit" form or factory assembled! Nothing like building "kit test equipment" to build your K1 or K2 kit - very much in the Heathkit spirit of doing things. Only thing to watch out for - I was told by a few builders not to rely on it too much when measuring the toroids - trust the manual and the proper # of turns, etc.,. There were discrepancies between the measured L and what the manual stated the L should be, but my K2 worked FB following the instructions exactly. Paul KB9YVP "Jonathan Taylor, K1RFD" wrote: > All of this discussion makes me think it would be great to have a > capacitance meter on the bench, yet this is something most hams probably > don't have. +++++++++++++++++++ Reply-To: From: "Ron D' Eau Claire" To: Subject: RE: [Elecraft] Another K2 Capacitor Question.... Date: Sun, 6 Jan 2002 09:21:50 -0800 Jonathan, K1RFD, wrote > All of this discussion makes me think it would be great to have a > capacitance meter on the bench, yet this is something most hams probably > don't have. > > Has anyone seen a simple circuit which would allow capacitor values to be > checked using, say, a signal source, an RF probe, and a DMM? In other > words, a "capacitance probe"? Testing caps "in circuit" with some sort of probe is pretty hard since the stray capacitance of the other components and PCB often exceed the value of the capacitor being checked. More commonly a 'bad' capacitor is detected by its effect on the overall operation of a circuit. Out of the circuit, a capacitance checker is very useful. You may be right that many Hams lack one although I have gotten used to a capacitance testing feature in most modern DMM's. I have two DMM's and both of them, a Fluke and a relatively inexpensive (about US $70) Radio Shack unit provide capacitance checks. The Radio Shack meter does a good job on anything from electrolytics of hundreds of microfarads down to values of a few pf, if you subtract the stay capacitance reading of the meter itself. So if you are thinking of upgrading your DMM, getting one with a built-in capacitance meter might be the way to go. Also, I've gotten "spoiled" by the newer DMMs that let me plug in an unknown bipolar transistor and it immediately gives me both the hfe and the pinout! Ron AC7AC K2 # 1289 +++++++++++++++ Date: Sun, 06 Jan 2002 04:13:38 -0500 To: elecraft at mailman.qth.net From: "Jerry W. O'Dell" Subject: [Elecraft] Cap meters Lots of digital multimeters have capacitance as a standard feature. They're not terribly accurate, though. And the grid dip meters will do inductance, granted with great trouble. I have a Kelvin and Radio Shack that both do a creditable job of checking capacitance. 73 jerry w8gnd ++++++++++++++++