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Re: [TenTec] In praise of older technology AM transmitwithTenTecrigs

To: <bcarling@cfl.rr.com>, "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Subject: Re: [TenTec] In praise of older technology AM transmitwithTenTecrigs
From: "Bob McGraw - K4TAX" <RMcGraw@Blomand.net>
Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Sat, 1 Mar 2014 10:41:57 -0600
List-post: <tentec@contesting.com">mailto:tentec@contesting.com>
Depending on the filter installed, there is a jumper that changes the stage gain to make up the loss in the filter. Different filters have different amounts of insertion loss. It just could be the jumper is not correct. Or the filter may be defective or may not even be the correct filter. Many hams believe "if it plugs in, it should work". Ha Ha!

My Omni VI Plus has a #220 - 2.4 kHz filter in the N-1 position, a #218 - 1.8 kHz in the N-2 position. Filters # 216, # 217 & #219 require the jumper to be in the high gain position. Filters #218 & #220 us the low gain position for the jumper. This is for the 9 MHz IF.

The 6.3 MHz IF has the standard 2.4 kHz then the #288 1.8 kHz for SSB and the #285 500 Hz for CW and the #282 Hz for CW.

Regarding the S meter, it needs to be calibrated. It requires two signals levels, one being 1.60 uV to set the offset value such that the meter reads S-3 and then 50uV to set the meter to indicate S-9. There is interaction between the two adjustments. Repeat the process 3 or 4 times as necessary. This is done on 20M.

73
Bob, K4TAX


----- Original Message ----- From: <bcarling@cfl.rr.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, March 01, 2014 9:53 AM
Subject: Re: [TenTec] In praise of older technology AM transmitwithTenTecrigs


I need to open up my OMNI 6 Plus and have a good look at a coupe of things:

1) The filter in the N-1 position is NOT at all good. It dramatically INCREASES the QRM in a contest whether using SSB or CW. I am really curious to know what is in there. Ther eis no N-2 filter. The only other filter I have is the normal 500 Hz one. It
seems to work OK.

2) Scotch S-meter never reads above S7

Thoughts?

On 27 Feb 2014 at 7:31, Brian Carling wrote:

Which model number INRAD filter do I want for 600 HZ roofing in my Omni VI Plus please ?
Sorry for my ignorance but they list so many, and I want to be sure...

Of course, I could also put the money toward saving up for a nice OMNI VII !

Best regards - Bry Carling AF4K



> On Feb 26, 2014, at 4:22 PM, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> > wrote:
>
> Let me put some meat behind my previous post:
>
> Filter:.....TenTec....INRAD....INRAD
> Filter:.....Stock.....600Hz....2400Hz
> -------------------------------------
> - 2 kHz.....79dB......94dB.....85.5dB
> - 5 kHz.....82.5dB....97dB.....95.5dB
> -10 kHz.....86.5dB....98dB.....96.5dB
> -20 kHz.....95dB......97.5dB...97.5dB
>
> As you see, at 2kHz spacing, the BDR3 improves by 15dB with the 600 Hz > INRAD
> roofing filter.
> There is nothing you can do to an OM7 or IC7800 (within reason) to come
> anywhere near this level of performance.
> NOTHING!
>
> The fundamental difference here is the technical difference between > upward
> conversion and downward conversion.
>
> AT THIS POINT Rob always jumps in and points out that it is not > impossible
> with upward conversion.
> Indeed the PT-8000 achieves it, but at a $17K price tag.
> That's why I added the modifier, "within reason".
> For those of us who work for a living, $17K is beyond reason!
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Rick -
> DJ0IP / NJ0IP
> Sent: Wednesday, February 26, 2014 6:38 PM
> To: n4py3@earthlink.net; 'Discussion of Ten-Tec Equipment'
> Subject: Re: [TenTec] In praise of older technology AM
> transmitwithTenTecrigs
>
> The Omni VI with the INRAD roofing filter is about 15 dB better than > the OM7
> or 7800.   Really no comparison.
> There most certainly is a difference but you will probably only notice > it in
> a side-by-side comparison during a BIG contest; not in every day life.
>
> I don't recall Rob ever testing the VI with INRAD.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
> man/listinfo/tentec
>
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