G3KEV worked OH3LYG daytime at 1117utc/241199. Report 559 each way. This report was down only one S point compared to a qso at 2107utc/211199 evening. 73 de Mal/G3KEV
Spoke with Jack agn tonight. He es MM0ALM have been trying for normal cw qso. Jack has heard MM0ALM but not well enough for contact . Glad Dave/MM0ALM is making it across to Jack. That is a good sig
He is wrong! Theory and experiment confirrm that 1W ERP is 1W ERP irrespective of the sise /height of the ant. (or anything else for that matter). You must know something about LF/MF antennas that t
He is wrong! Theory and experiment confirrm that 1W ERP is 1W ERP irrespective of the sise /height of the ant. (or anything else for that matter). There is a difference. The big antenna lauches the
Well ............. Just installed a version of the Decca guard circuit on the 600W PA, and its performance is seriously impressive ! Still using the cheap and nasty IRF840 FETs with just a minimum o
Merry Christmas to all experimenters on LF. Unfortunately I am otherwise engaged at present and cannot participate with the VE1ZZ experiments, but now that he is being heard in EU by several amateurs
Still the same power, but wet surroundings may make the antenna less efficient. The load R has risen so looks valid. The BPSK message is stored in PIC so won't change in the immediate future, I was
If you live near a fishing port go to the port equipment shop and get some crab pot spinners. These are light weight polysterene devices, white in colour, shaped like a flat dog bone and very strong
Sounds like the LF source book of a couple of years ago. Most of the information was obsolete and bore no resemblence to the achievements taking place when it was published. I think 23 km was the re
Hello. Thanks to all that supplied info about my transistor query. I had lots of replies direct and via the reflector. This info is much appreciated. 73 and agn tnx de Mal/G3KEV
Hi All. Does anyone know if VE1ZZ is active or listening on 136. I have worked him numerous times on 160m and heard he was interested in LF but all has gone quiet lately. At times CFH is blowing my h
Hi Mal, My data tables show the 2N6674 to be an NPN silicon transistor, with the following params: Max reverse voltage: 300 I max 20 amps P 175 watts gain 8 - 20 at 10 amps working range up to 15 MH
Towers transistor selector has it as: NPN, Si, TO3, 300V Vce, 15A max, 175W dis, Hfe of 8 at 10A, Ft of 15MHz. Made by RCA originally. Sounds a useful device. FETs are better though! 73. Dave G3YXM.
Hello All The method of using an HF frequency, dividing down then using high power fets in class D or E then a LPF is not totally satisfactory and only permits cw mode. Keying this type of tx is also
Hi all Does anyone know what a 2N6674 transistor happens to be? I have 4 of these devices out of a SMPS rated at 600w. These are Motorola. Your help appreciated de Mal/G3KEV
Andy and All The parasitic diode is no good in this configuration for catching the spikes from what I call the transient soak choke, I use separate clamp diodes up to the rails effectively 'crosing o
G3KEV wrote: the band was extended for a total of 3 years it was still the policy in spite of the fact that all the existing permits holders that were active were all south of Birmingham. For genuin
G3KEV wrote: the band was extended for a total of 3 years it was still the policy in spite of the fact that all the existing permits holders that were active were all south of Birmingham. For genuin