
	Tranceiver modifications file for high speed MS CW keying
       ----------------------------------------------------------
	(All tranceivers do NOT need to be modified)

ICOM    IC-720A : Main unit :Change C 8 and C 7 to 10nF. RF unit: Change 
	C 165 to 1uF 16V.
	
	IC-211 & IC-251: Change C238 (33uF) to 4.7 uF 16V. (IC-245E?)

	IC-970: Low power model works, hi power does not.

Kenwood TS-711: IF unit: Change C44 (2.2uF) to 470nF. (info ON4ADC)
	
	TS-450S & TS-690S: see Dubus No.4 1992, page 51.
	
	TR-751E: Remove C83 0.1uF tantalium capacitor and replace with 10nF
	Ceramic capacitor. Remove top cover, locate the PLL, TX-Unit 
	It's the only complete visible PCB in the back of the radio. 
	Remove the 5 screws, disconnect the grey coaxial cable 
	(To final unit), disconnect J2 (on the left of the PCB), J6,J8 and J9 
	(on the right of the PCB). Now you can take out the PCB 
	(with some feeling). Right next to J9 is C83. Just solder 
	it out and put a 10nF ceramic in place. Reassemble your radio 
	in reversed order and it should run on High speed CW. Tested 
	this modification and it works here up to 4000lpm and before 
	modification absolute maximum of 1200lpm. (info PE1OGF)

	TS-790E: Unit X59-3480-00 G/18 (nr key jack): change C221, a 1uF SMD 
	tantal, to 100nF ceramic. Good up to 1500LPM. (info ex. DH1NAD)
	
	TS-120V: RF-unit: Remove C63 C64 C70 C62. If it still does not 
	work, remove also C46 C48 C53 from balanced modulator.( info DL3IAE)
	
	TS-850SAT: On IF-Unit, (X48-3080-00): Change C202, from 2.2 uF 
	to 1 uF/50V tantal. C202 must be switchable to preserv full break-in 
	keying on HF.
	On RF-Unit, (X44-3120-00): Change C248, from 0.1 uFF to 0.033 uF. 
	Change C249, from 0.047 uF to 0.015 uF.
	This increases keying speed from 750 LPM to over 1200 LPM.(info DK9ZY)
	

Yaesu   FT-767: Remove with cutters  C14 C15 and C16 from control unit
	leaving as long as possible the old capacitor leads. The unit 
	is located in the middle of the rig and is not easy to access.
	You must remove many screws to expose the unit. Replace with 1.5nF 
	(was 2*22nF and 10nF). Bend wires to a loop and hook new capacitors 
	there and swiftly solder one leg at a time.(info LA7DFA)
	(tested by OH7PI)
	
	FT-726R: Some work, some don't.....
	
	FT-736R: My own works without any modifications up to 2000...3000lpm.
	It was manufactured in later half of 1994. Someone complains that 
	with VOX an older one will not work above 700LPM, could he have an 
	RFI problem? You may try to reduce C82 value on TX unit (4.7uF).

	FT1000MP is running up to 2000 lpm without any modifications. 
	(info DH8NAA)


MORE MODIFICATIONS NEEDED. IF YOU KNOW ONE NOT ON THE LIST, SEND IT TO ME
ON PACKET: OH5IY@OH5RBG.FIN.EU or on E-mail    PLEASE!!!/TNX 


You only have to remove C83 0.1uF tantalium capacitor and replace with 10nF
Ceramic capacitor

- Remove top cover

- Locate the PLL, TX-Unit (It's the only complete visable PCB in the
  back of the radio. 

- Remove the 5 screws

- Disconnect the grey coaxial cable (To final unit) disconnect J2 (on the left
  of the PCB) J6,J8 and J9 (on the right of the PCB)

- Now you can take out the PCB (with some feeling) 

- Right next to J9 is C83 located just solder it out.
  and put a 10nF ceramic in place

- Put your radio together just in reversed order and it should run on 
  High speed CW.


I've just tested this modification and it works here up to 4000lpm and before
modification absolute maximum of 1200lpm.

de John pe1ogf @ pi8zaa.#nbo.nld.eu
(Ask John what radio this is?)
