Hardware anomalies that are considered normal
From Zerobeat
1. With a first IF of around 8 MHz, how can the receiver be general coverage? Will there not at least be hole in the coverage around the IF frequency?
General does not mean continuous in this case. There is a small gap at 8.215 MHz. You may be able to tune to this frequency, or not, depending on the firmware. There is a trap circuit to suppress response at this frequency, so the receiver won't work very well within several kHz of 8.215 MHz if it does allow you to tune there.
Acknowledged by Elecraft as normal operation.
2. There are ONLY five (5) spots for crystal filters in the K3? What if the user wants 250, 500, 1.8, 2.2, 2.4, and 2.8 filter installed? Crystal filters are not used in the K3 to determine final selectivity. Whereas in the above scenario one would have needed all of the filters above to provide superior performance with previous generation radios, all of the listed bandwidths and more are included in the stock K3 at about the same level of performance that one would be used to in previous generation transceivers after buying all those crystals.
Acknowledged by Elecraft as normal operation.
The exception with K3, is that if you want to operate FM, you need to buy a 15khz cystal filter. If you want to operate AM, you need to buy a 6khz filter. In some cases the 15khz filter may be usable on AM.
3. The K3 copies general coverage frequencies, but on some of them the signals are greatly attenuated. Is this normal?
The base K3 will provide acceptable performance on most SWL frequencies, however for optimal performance on all frequencies, the optional band pass filter (KBPF3 General Coverage RX Filter Module) must be purchased and added to the radio. Without the optional filter installed the amateur band filters will attenuate some of the frequencies of general coverage.
Acknowledged by Elecraft as normal operation.
4. The K3 buttons in close proximity to the one I push also depress inward, as if the board is flexing. Is this normal?
From Elecraft: We measured the amount of flex. At the point of maximum flex, the board moves about 1/32" of an inch. The board is securely held in place, but the nearest supports are points about 2.5 inches below and almost 3 inches to the side of the A/B button.
That amount of movement is not enough to be of concern at all.
Here is a possible solution, suggested by Douglas Zwiebel, KR2Q
- Read Fixing_The_Flex
Acknowledged by Elecraft as normal operation.
January 18, 2008
K3 I/O Caution
This worked for me too. An added tip is one I got from Wayne when experiencing RF feedback on PSK31: Seat the two KIO3 rear panel connector boards (3.5mm fems, and also the RCA / 1/4" phono) so that there is a slight amount of interference with the screw-on panel. This allows the grounds for the jacks to make best contact with the 3.5mm plugs. It takes a little jiggling to get the fit to come out just right, but you need the jack bodies (sleeve is ground) to jut out just a little bit to get proper contact.
Matt, W6NIA
I've been having intermittent computer problems with the K3 connected ever since installing the K3 on the operating desk. The ultimate disaster occurred during the RTTY Roundup when the computer shut itself off and lost my log with approximately 1100 QSO's. After making various attempts to block RF from entering the computer, I ran across what appears to be the solution.
The DB9M connector on my serial cable used for K3 I/O had the standard threaded studs installed. These had to be removed to allow fitting to the K3 I/O port with its own threaded studs. With the studs removed, the connectors mated, but nothing but friction to hold them together. I wondered if perhaps the shells were making intermittent contact. I next drilled through the connector body where the studs were removed and inserted a spare pair of thumb screws that were left over from a DB9F connector. With these screwed into the K3's threaded studs to secure the connectors, I've not had any further RF problems with the computer.
Bob Patten N4BP
