RM KL400 problem
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Re: RM KL400 problem
I bought some 68 ohm 5 watters from Ebay last week...8 for a fiver.
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- Phoenix
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Re: RM KL400 problem
Make sure they are not wirewound resistors, some wirewounds can have enough inductance to effect the feedback loop.
W8JI
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
Re: RM KL400 problem
Hi. Dont forget to pickup some hd.Teflon wire n rewind them transformers .. pce n 73'
- Phoenix
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Re: RM KL400 problem
Hi there can you explain the reasons for teflon and the re-wind thankyou
26TM114
Re: RM KL400 problem
Hi looking at your pic of burnt cap/resistors / and bad transistors. . more than likely wire's in transformers are rf cooked ie shorted out. besides you going to rebuild it its a gd idea to redo transformers anyway's while you at it.pce n 73's
- Phoenix
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Re: RM KL400 problem
Is it just a matter of copying the length of wire and number of turns ? cheers
26TM114
Re: RM KL400 problem
Hi Yes. .. its a gd General rule of thumb to go by ..when you dont have a schematic to go by ..but if you hav right schematic for it id would go by schematic /service manual for correct number of turns to be 110% accurate n cheers n 73's
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- astradyne
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Re: RM KL400 problem
Not sure if it will be of any help, but here are a few snaps of the inside of mine. To my knowledge it hasn't been tampered with.
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Never, ever, ever....bloody anything ever!
Far too many radio's to list here. But I do own a legal one...
Far too many radio's to list here. But I do own a legal one...
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Re: RM KL400 problem
Andi, That does not look standard to me,
somebody changed the 10ohm B/E resistors for larger 12ohm tacked on top of board,
modded the bias circuit for some thermal tracking,
power rail decoupling caps have been changed for larger caps,
feedback resistors are typically baked beyond readability & input resistor looks baked.
somebody changed the 10ohm B/E resistors for larger 12ohm tacked on top of board,
modded the bias circuit for some thermal tracking,
power rail decoupling caps have been changed for larger caps,
feedback resistors are typically baked beyond readability & input resistor looks baked.
W8JI
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
- astradyne
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Re: RM KL400 problem
I have no idea Mr. W.wa10 wrote:Andi, That does not look standard to me,
somebody changed the 10ohm B/E resistors for larger 12ohm tacked on top of board,
modded the bias circuit for some thermal tracking,
power rail decoupling caps have been changed for larger caps,
feedback resistors are typically baked beyond readability & input resistor looks baked.
It had intact warranty seals when I purchased it, which I broke to take these pictures. Obviously they can't have been original...
It does sound like some positive mods have been done to this particular amp then? It certainly works very well although the pre-amp isn't the best.
Any ideas on the value of the input resistor? It may look baked but be working fine, but for a few pence it could be worth replacing it.
Never, ever, ever....bloody anything ever!
Far too many radio's to list here. But I do own a legal one...
Far too many radio's to list here. But I do own a legal one...
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Re: RM KL400 problem
The input resistor far left of bottom pic should be 150ohm, the resistor on the opposite side of the power setting board should be 27ohm or 22ohm if it has one,
the large baked feedback resistors should be 68ohm.
most RM amps i have seen have resistors that have been at least slightly smoking, some of them still work with parts that got so hot they dropped out of the board.
the large baked feedback resistors should be 68ohm.
most RM amps i have seen have resistors that have been at least slightly smoking, some of them still work with parts that got so hot they dropped out of the board.
W8JI
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!
"An antenna with a poor ground using few radials cannot have a support mast grounded to the radial common point (at least it shouldn't if designed properly) There is no exception to this!