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Author Topic: Additions to my 857D advice please  (Read 7706 times)

2E0BSS

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Additions to my 857D advice please
« on: August 14, 2007, 02:30:24 PM »

I have a Yaesu 857D, which I am on the whole very happy with, although the filtration isn't great.

I am thinking about adding a few of the extra filters such as ::

TCXO-9 High Stability Crystal 0.5ppm
DSP-2 (Spare DSP) unit

Now my question is what benefit will there be in fitting the two or will it be more benefit to buy:

ANEM bhi Amplified Module

Small readout available at the following link.

http://www.radioworld.co.uk/~radio/catalog/anem-amplified-module-p-3545.html?osCsid=f4b65f6332540f9ef94f80e877d3d50d

As I'm suffering 7-9+ noise due to my location this there is nothing I can do about unless I switch on at 3am then I only get 6 noise from 80-15mtr 20 is terrible as is 40. My attenna cannot do top band so I don't bother with it.

Charlotte 2E0BSS
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AI4NS

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Additions to my 857D advice please
« Reply #1 on: August 14, 2007, 08:31:13 PM »

The TCXO is a high stability option to improve frequency accuracy and drift. It will do nothing for receive. Is your rig new? THe new ones have DSP built in, not an option. The other thing you referenced is an audio DSP module, but I don't know anything about them. ClearSpeech and others may be better. As far as noise, the optional Collins filters can help by reducing the bandwidth the receiver is seeing, helping reduce the noise. DSP doesn't like too narrow of a filter selection, but that would not be a problem in this case.

Mike
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WW5AA

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Additions to my 857D advice please
« Reply #2 on: August 15, 2007, 08:53:54 AM »

It took me a long time to get mine adjusted properly...At first I was not very happy with the receive. It was more operator error however than the radio. With all the menu driven options finally figuered out and set properly the 857D really plays well. A quality headset or speaker will also go a long way.

73, de Lindy
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2E0BSS

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Additions to my 857D advice please
« Reply #3 on: August 15, 2007, 09:16:43 AM »

My 857D is a year old. It's got some of filters fitted but no IF filters, can't find those either unless they're the SSB/CW collins ones at £110 each.

So in short terms an external DSP unit would outway the internal fitted ones. I'm having a look at Clear speech to see if it's what I need

Charlotte 2E0BSS
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2E0BSS

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Additions to my 857D advice please
« Reply #4 on: August 15, 2007, 09:17:49 AM »

Am I right in thinking that the extra DSP is mainly for the older non D version of the 857? so not really any benefit to me at all

Charlotte 2E0BSS
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WW5AA

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Additions to my 857D advice please
« Reply #5 on: August 16, 2007, 01:13:17 PM »

Charlotte,

I believe that you would be better of finding the cause of the high noise level. The height of your antenna above the roof might be a problem, or the RFI from power lines or other things in the building. DSP, filters, noise blankers can only go so far when the RFI reaches the level you are having. Even if the problem can not be fixed, one type or other of receiving antenna may help.

73, de Lindy
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2E0BSS

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Additions to my 857D advice please
« Reply #6 on: August 16, 2007, 04:48:32 PM »

You're right finding the cause and curing it would be great but it's not possible for the following reasons

I live in a block of flats that are steel framed and the antenna, half size G5RV made to resonate on 20m, cannot go much higher due to my local authorities restrictions. We are going to try to get the antenna a few feet higher to cut the noise a touch but I'm not going to get rid of it totally.

Charlotte
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N0NOB

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Additions to my 857D advice please
« Reply #7 on: August 16, 2007, 05:19:29 PM »

Checkout this web site if you have not done so.

http://radio.bhinstrumentation.co.uk/
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WU6X

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Additions to my 857D advice please
« Reply #8 on: November 08, 2007, 07:15:35 AM »

I agree with another post ... you need to learn how to adjust the radio, DSP especially, can help you with noise. It took me a full two weeks of tweaking before I was REALLY happy with my new radio. Factory settings are not optimized for many things, for example, adjacent channel (SSB) interference.

You can help the receiver be much better at rejecting nearby SSB signals by changing the following:

Menu-047 DSB LPF CUTOFF comes set at 6000hz, but can be adjusted as low as 1000. I set this to 2450hz (the manual recommends 2130-2770).

This made a remarkable difference on loud adjacent signals. The receiver acts more like a desktop radio now, with loud signals not heard if more than 2.5-3khz away, and just barely at 2khz.

Also, use the noise blanker (NB), and set the DSP "DNR" to "8" and use that too. Good luck and 73, WU6X
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