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Hi, I'm Ivan Shor !

This page about my hobby : Amateur Radio

on the HF, VHF , UHF , SHF band.

Well, but what about my next hobbies? - Sail, of course.

New Designs & Articles

Second CW filter in 1st IF of TS-830

RF transformer with separate coil and only connection by magnetic field

Retuning of CELWAVE Power Dual Isolator/Circulator CD150-B from 163 to 144 MHz

Look for more informations about retuning here.....


You can use low cost microphone by Motorola HMN3596A (from GM-300 and other UHF TRX) for TS830. You will make middle spectrum of your audio signal from 250 Hz to 2800Hz .


CW iambic electronic key for TS 520/530/820/830 and other tranceiver



Modification of R-140 Power Amplifier for two GK71 with grounded grids

_RF Voltmeter and Dummy Load 50 Ohm for QRO


2 Time delay SEQUENCER, now with USB !

Dual band FeedHorn for 1296 and 5760 MHz

New elements LC for expand band of tune in Smart Automatic Antenna tuner

The Lightning Protection for Rotors

If you want to buy assembled and tested board please look at K6VHF`s info here

Download description of LPR

New Magic QRP SWR Bridge v.3

If you want to buy KIT of Magic Bridge or assembled and tested board please look at K6VHF`s info here


If you want to use your old HF tranceiver in VHF in EME or MS QSO - you must increase stability of frequency. For example - i use my old IC745 with my 144/28 XVTR . I have good total value of frequency stability for long sending cycle without TXCO. You need only some a bit of polypropylene for VCO, 2nd LO and LO.

In old tranceivers often was problem with switchknobs XIT/RIT.

Good idea is - to use old switchknobs XIT/RIT for control of good relay. Now only clear of relay ladder with good contact will be control XIT/RIT . For example - i use russian relay RES-49 in easy layout !

Repairing old potentiometers

 The change of original components when restoring old radio or transceiver sets is always an unpleasant. In the case of potentiometers it is difficult to find double original potentiometers for RF/AF or Mic/RF PWR.

 If you hear rustling in old potentiometers of your old transceivers you need repair them with oil. My practice is to use syringe with solid oil + spirit. Usually I use russian solid oil ÖÈÀÒÈÌ-203 (ÃÎÑÒ8773-73) . You can use SIMNIA 0, PETROLEUM JELLY S68OO,Mobiltemp SHC 100, AEROSHELL 15A or or good quality machine oil.

 You don`t must to open potentiometers, you must only press out some oil with spirit into potentiometers. You must to turn the potentiometer minimum 20 times from end to end. The solid oil hits to center contact and will protect contact near axis.
 This technique is very effective and, usually, these potentiometers will still perfectly efficient. But i know what in 5% of cases where the resistive surface has been damaged and way with repair potentiometer by oil does`t work. More info you can look here....

Smart Automatic Antenna Tuner for portable QRV


Magic QRP SWR Bridge

Easy modification AM broadcast receiver


After modification ... Air 40m band Air 17m band


QRP CW Transceiver

+ Modification + CW filter


USB Power Metr

Measure power from 10 MHz to 12 GHz !

HAMs who owns this Power Meter :



This bug want to help us in Field Day

Just see more about.....



VHF : UHF : SHF Cluster __

SK6AW DxSummit F5LEN



DX QSLs has arrived

432 and 1296 MHz TROPO

5760 MHz 587 km TROPO




You can send me FeedBack or Sked

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