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FT-757 GXII alignment....
Has anyone any info on servicing one of these?
The power control is out of alignment (about 3/4 of the way up it suddenly jumps into TX at full power, with it being very sensitive to get any control between full and no power). Possibly a bias problem on the PA? And the power meter needs re-aligning. And the FM deviation is too high. Can anyone point me towards the internal pots? Thanks, Sam M1FJB |
FT-757 GXII alignment....
Hiya Sam, I had one of these, I am sure the FM pot is on the 'local'
board, which is the one with the patch/ptt/CAT sockets on. VR02 I am sure, and it feeds the fm af amp transistor, q2008. As for the power control, they are very 'jumpy', all on or off, and very narrow over the operating range, sure yours is just as they are. I also still have the mobile mount for it in the loft, I think!!!!!!!! Cheers, Fred G4ZWI |
FT-757 GXII alignment....
Hi Fred...
Ah, never mind then, I'll have to live with it (well not me, I'm asking on behalf of a friend). Any ideas about the meter though, that needs re-calibrating. Sam "G4ZWI" wrote in message oups.com... Hiya Sam, I had one of these, I am sure the FM pot is on the 'local' board, which is the one with the patch/ptt/CAT sockets on. VR02 I am sure, and it feeds the fm af amp transistor, q2008. As for the power control, they are very 'jumpy', all on or off, and very narrow over the operating range, sure yours is just as they are. I also still have the mobile mount for it in the loft, I think!!!!!!!! Cheers, Fred G4ZWI |
FT-757 GXII alignment....
Never had to tweak that one Sam. There is a preset near the meter
driver circuit, (An6552, Q51, on the R.F. board.) That may be the one. There is a 'pot' to set the FSD of the meter on Tx (for SWR forward reading, obviously you set it to full scale, then set the swr switch to reverse.) It is not that this control has been set too far up?? (Its on the back of the unit, under the antenna socket, marked 'fwd set'?) Best of luck, mate, I have got a few bits of cct diagrams if you are really stuck, and may help.... Fred |
FT-757 GXII alignment....
the full ervice manual is on mod.dk site
the power variable on the front panel always was 'iffy' though a squirt of cleaner (not WD40) might help. dont forget as the other gent says, the SWR pot on the back will effect the meter PO scale. also it is caled into 50R so will not read correct of an aerial or ATU. as such. if you wish help pse ask done loads and own one since 1985 mike "Samuel Hunt" wrote in message ... Has anyone any info on servicing one of these? The power control is out of alignment (about 3/4 of the way up it suddenly jumps into TX at full power, with it being very sensitive to get any control between full and no power). Possibly a bias problem on the PA? And the power meter needs re-aligning. And the FM deviation is too high. Can anyone point me towards the internal pots? Thanks, Sam M1FJB |
FT-757 GXII alignment....
Samuel Hunt wrote: Has anyone any info on servicing one of these? The power control is out of alignment (about 3/4 of the way up it suddenly jumps into TX at full power, with it being very sensitive to get any control between full and no power). Possibly a bias problem on the PA? And the power meter needs re-aligning. And the FM deviation is too high. Can anyone point me towards the internal pots? Thanks, Sam M1FJB Have a look on this url, the full workshop manual can be downloaded for free http://foxtango.ham-radio-op.net/Eighties/Eighties.htm regards Dave |
FT-757 GXII alignment....
wrote in message ups.com... Have a look on this url, the full workshop manual can be downloaded for free http://foxtango.ham-radio-op.net/Eighties/Eighties.htm That is a useful link. I see they have manuals for the FT101 as well: http://foxtango.ham-radio-op.net/FT101/FT101.htm Wasn't there someone who couldn't tune the PA on one of these as some pages were missing from his manual? __ 73 Brian www.g8osn.org.uk |
FT-757 GXII alignment....
Brian Reay wrote: I see they have manuals for the FT101 as well: http://foxtango.ham-radio-op.net/FT101/FT101.htm Wasn't there someone who couldn't tune the PA on one of these as some pages were missing from his manual? Isn't that the same chappy who's radio scheme enjoins potential candidates to 'repair their rigs with gusto' (or some such claptrap phrase) but neglects to mention that he only advises they do so to low-powered transistorised rigs, and avoids compact valve PAs with 600VDC on the anodes? from Aero Spike |
FT-757 GXII alignment....
Wasn't there someone who couldn't work out the trivially simple
task of how to thread a wire through the tubes of a roof rack? Brian Reay wrote: Wasn't there someone who couldn't tune the PA on one of these as some pages were missing from his manual? |
FT-757 GXII alignment....
Wasn't there someone who couldn't achieve the trivially simple
task of differentiating between the male and female version of Anderson "Power Pole" connectors? ISTR it was the same fool who couldn't tell one end of the resistor colour codes from the other and hence posited that resistors were polarised? What a silly boy! Brian Reay wrote: Wasn't there someone who couldn't tune the PA on one of these as some pages were missing from his manual? |
FT-757 GXII alignment....
Not so much "avoided", more a case of being too lazy or too
stupid, or both, to be able to tackle and pass a test targetted at 14-year-olds and which 14-year-olds were taking in their stride? Nedlar wrote: On 19 Feb 2006 04:44:27 -0800, "Plod's Conscience" wrote: Wasn't there someone who couldn't work out the trivially simple task of how to thread a wire through the tubes of a roof rack? Wasn't that the same person who avoided taking a trivially simple Morse test for 20-odd years and then used the farcical M3 route in order to get on HF? |
FT-757 GXII alignment....
on 19/02/2006 13:08 Chippenham Breaker (CB) said the following:
Not so much "avoided", more a case of being too lazy or too stupid, or both, to be able to tackle and pass a test targetted at 14-year-olds and which 14-year-olds were taking in their stride? and how old were _YOU_ when you passed? ....(_!_)... |
FT-757 GXII alignment....
Nedlar wrote:
On 19 Feb 2006 04:44:27 -0800, "Plod's Conscience" wrote: Wasn't there someone who couldn't work out the trivially simple task of how to thread a wire through the tubes of a roof rack? Wasn't that the same person who avoided taking a trivially simple Morse test for 20-odd years and then used the farcical M3 route in order to get on HF? Who was it that avoided it for 14 years? -- huLLy Tel: 07976 123278 ICQ 136-987-925 |
FT-757 GXII alignment....
Nedlar wrote:
On Sun, 19 Feb 2006 13:42:56 -0000, "huLLy" wrote: Who was it that avoided it for 14 years? No idea. It can't have been you because you remain a 2nd-Class G7. Thank you for reminding me. Whatever would I do without you? -- huLLy Tel: 07976 123278 ICQ 136-987-925 |
FT-757 GXII alignment....
"huLLy" wrote:
Who was it that avoided it for 14 years? g7--- was issued when ??? |
FT-757 GXII alignment....
zBBPK wrote:
"huLLy" wrote: Who was it that avoided it for 14 years? g7--- was issued when ??? 1987 but I never avoided it ;) -- huLLy Tel: 07976 123278 ICQ 136-987-925 |
FT-757 GXII alignment....
You avoided a trivially simple Morse test. I suppose you had no interest in HF eh? ( apart from freebanding ?)... Tee hee !.......nice one..... |
FT-757 GXII alignment....
"Three Cheers for PC Fuller!" wrote:
zBBPK wrote: "huLLy" wrote: Who was it that avoided it for 14 years? g7--- was issued when ??? 1987 but I never avoided it ;) bbbbbbbbbwwwwwwwwwwwwaaaaaaaaaaaaaahhhhhhhhhhhhh next thing you'll claim is that you had no interest in hf !! |
FT-757 GXII alignment....
Nedlar wrote:
"huLLy" wrote: 1987 but I never avoided it ;) You avoided a trivially simple Morse test. I suppose you had no interest in HF eh? ( apart from freebanding ?)... snap! |
FT-757 GXII alignment....
zBBPK wrote:
next thing you'll claim is that you had no interest in hf !! Correct, and I still don't. -- huLLy Tel: 07976 123278 ICQ 136-987-925 |
FT-757 GXII alignment....
I had one of these and worked 10m DXCC in 90s... later had to sell it and
just now have a used one from ebay. I took apart the dial that was stuck and repaired the optical tuner mechanism. Now I don't know if I have a large SWR or if the rig is sick. It jumps freq' when the RF output power is turned up. I was hoping to see some more tips and helps but the thread seems to have been taken over by some sand pile kids with no help other than flaming any post. Any ideas why the rig jumps freq? Restarting from scratch. No Bird or Freq meters yet. Odd this was run on homebrew LOL Thanks 73 Gary K4TWO "Samuel Hunt" wrote in message ... Has anyone any info on servicing one of these? The power control is out of alignment (about 3/4 of the way up it suddenly jumps into TX at full power, with it being very sensitive to get any control between full and no power). Possibly a bias problem on the PA? And the power meter needs re-aligning. And the FM deviation is too high. Can anyone point me towards the internal pots? Thanks, Sam M1FJB |
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