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Slicker
Posted on Saturday, July 27, 2002 - 7:00 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

can someone tell me which model of the siltronix 90 will work with the browning golden eagle MKII i beleive it might be the 3 but im not sure, also i know you can mod them to work on diff radios can anyone tell what mods need to be done for the MarkIII and MarkII
Thanks in advance
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2600
Posted on Sunday, July 28, 2002 - 11:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Nope, the Siltronix type 3 won't. The Mark III SSB transmitter (the full-size one NOT the half-size MkIII AM-only)needs 16.270 MHz for channel 1. This is what the type "3" Siltronix VFO provides. The AM-only transmitter is different, whether it's a S-23, 23S9, Golden Eagle or Mark II. They all use a crystal that runs ON THE CHANNEL you are using. This means that a slider has to deliver YOUR RECEIVER frequency into the crystal socket. More to the point, it has to be UNKEYED so you can hear. The Mark III SSB slider is feeding 16 MHz or so, and the receiver can't hear that, so it doesn't have to be keyed (or unkeyed). I have seen the PAL slider adapted by feeding a keying wire into it from the SPOT switch in the transmitter. It's a little messy, and the PAL has to be modified in two ways. First, to put it onto 27MHz output in the first place (takes a 22 MHz crystal and other stuff), second to add the keying circuit both inside the slider and inside the transmitter.
Glenn used to sell a converter for his slider that worked in an AM-only transmitter. It had a 10MHz crystal and a mixer circuit. The Glenn was set to feed 10 MHz below your channel frequency (wouldn't bother the receiver). The slider fed into the adapter, which was hooked up to the spot switch, and fed into a crystal socket. This way you only got 27 MHz when you pressed te SPOT button or keyed the mike, but NOT while receiving.
We have installed a sample batch of my version of this converter. So far so good, according to the customers who agreed to be "guinea pigs" for it. The installation instructions are nowhere near ready for 'prime time'. There's no date scheduled to complete them, so looking for an original Glenn converter might be faster.
73
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Slicker
Posted on Tuesday, July 30, 2002 - 7:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks So much for the info on the siltronix. there is another qeustion i had about vfo's i have a pal model H and i also have a markIII that has never been modified in any way as a matter of fact it doesn't recieve above 28 i was wanting to know if it is possible to hook up the pal to the receiver to increase the receive without doing a major mod with the crystals. i have the specs for the mod but wanted to avoid it if possible Thanks again
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2600
Posted on Wednesday, July 31, 2002 - 1:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Oops, Frank changed his model numbering scheme after my book was printed. It shows only the letters A,B,C and D, followed by a digit. I think the letter "H" on his later models was for 37 Mhz crystals, maybe 37.6 MHz for channel 1 ? Call Maycom (www.maycomcomm.com) for the 31.72 crystal to get channels 28-60 on the receiver. You'll have to rewire the band switch to make one of the 'XTL' positions into a new tuneable band. I think they have a set of instructions for that. You would have to modify it a LOT more than that to use the slider on the receiver, and then you would have TWO dials to read. I'm 95% sure the "H" PAL won't run on your Mark III SSB transmitter without being severely modified (new crystal, 3 new coils, 6 or 7 capacitors and resistors changed) to make it deliver 16.27 MHz at channel 1, like the Mark III SSB requires.
I've seen a couple of attempts at converting the receiver coverage without the band crystal, but I wasn't impressed by the results, at all. Both seemed to ruin bleedover resistance. Not a pretty sight.
I have a humorous picture of a converted digital PAL at http://my.core.com/~nomad/Pal3_19small.jpg
Yet another product not ready for "Prime Time", but removes the need for a frequency counter.
73
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Scrapiron63
Posted on Wednesday, July 31, 2002 - 6:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

2600 I believe you know the old Brownings. I have a small collection of them, 6 sets at the present.
My Mark II Transmitter was converted back when the 40 channels came out, another crystal bank just like the orginal was installed on the same shaft. A small switch toggles between the two banks. Also the extra crystal sockets on the second bank can be used for other channels. The Glen is the ideal way for the Mark III transmitter I think. However both of the ones I own now have the crystal conversion, it works pretty good, especially with the band spread pot expanded for extra slid, it will get the RC skips.
You lose SSB, but the Mark III ain't my choice for sideband. Every siltronix vfo I have used will have a more that normal harmonic. Someone that knows my voice, will hear me on the harmonic channel and think I am ignoring them it will be so strong.

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