[Elecraft] low pre-driver

Hi, When doing the 40-Meter Transmitter Alignment, I couldn't keep the output power in th 1-2 watt range. Turning the power all the way up only got up to .7 watts. I checked the output across the dumy load and it was practically non-existent (.007Vrms) though key-down was noticeably different

Re: [Elecraft] K2 low pre-driver

. Then put the heat sink back on and see if there is any change. BTW - you can consider the division between the pre-driver and the driver as being between the primary and the secondary winding of T1. 73, Don W3FPR Robert Greenwalt wrote: Hi, When doing the 40-Meter Transmitter Alignment, I

[Elecraft] K2 receiver problem and signal tracing question

Hi My K2 used to receive nicely. Good strong signals on various bands, I was able to use a noise generator and spectrograph program to tune the filters, etc. Then I added the ssb kit and receiving seemed to fall way off. I removed the kit, re-soldered the jumpers and resistor and still

[Elecraft] fun k2 debugging

So I have a K2 all put together. I thought it was receiving fine - I didn't try transmitting as I shamefully don't have CW down yet. I got the ssb kit and put it together and it didn't transmit. I stripped it out (jumpers back in place at W2, W3 and C167 is back in) and tried testing cw

[Elecraft] K2 problems

I completed the baseline k2 kit but I seem to have some problems: The Voltage measurements from pg17 of the trouble shooting section differs from what I'm seeing in the receive case: U4 5-pin should be 5 but I get 0 U4 7-pin should be 0 but I get 5 U5 1-pin should be 0 but I get 5 U5 2-pin should

[Elecraft] K2 VCO Alignment problem

Hi I've worked my way through assembling my k2 and I've reached a problem: Everything seems fine until the 4000 kHz, R30 - 6V alignment of L30. I can only reach 5.65V. I have verified D23-26 are the right part, oriented correctly. I have verified D21-22 are the right part and oriented

[Elecraft] K2 assembly debugging

I'm writing this in case others run into a similar problem. I got to the Alignment and Test, Part II and discovered my U6 pin 8 resistance was low (58.3 with 100 ohms required). I visually inspected but found nothing. I traced around doing resistance checks and found an unexpectedly low reading

[Elecraft] Hi current

I just installed my KPA 100 with the KAT100 antenna tuner. Every thing was working fine on all bands - until I attempted to tune on 40 meters. Suddenly I got an alarm and the panel is locked - I can't get to menu or any of the controls. The alarm is a continuous beeping. I removed the high

[Elecraft] KPA 100 resistance checks

I've built the KPA 100 up to the alignment and installation steps and made the resistance checks at J3+ and Q1 and Q2 collectors (all of which are supposed to be greater than 10k). The instructions state that the J3+ resistance may initially read 0 because a large electrolytic must charge up and