Keyboard Shortcuts
Likes
- YaesuFT847
- Messages
Search
Re: FT847 calibrate the V / U frequency
#tip
toggle quoted message
Show quoted text
On 2022-01-22 04:56 AM, Frank wrote:
|
Re: FT847 calibrate the V / U frequency
#tip
开云体育Your FT-847 is actually in spec.? Per the manual the frequency accuracy for the 847 is at best 2 PPM.? That translates to +/- 870 Hz at the center of the 70cm band, which is 435 MHz.? ?If you want to try and reduce the frequency error you will have to adjust the Reference Oscillator, which will take a very accurate frequency counter that can resolve down to 1 Hz at the reference frequency of 45.250 MHz.? An alternate method would be to Zero Beat the Reference Oscillator against WWV, but that might be a little less accurate. ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Frank ? HI all Does anyone know where in the radio I find and how can I correctly calibrate the right frequency? |
FT847 calibrate the V / U frequency
#tip
HI all
With the FT847 in VHF and UHF I have verified that they are off frequency of + 250Hz. Does anyone know where in the radio I find and how can I correctly calibrate the right frequency? 73 |
Re: Kuhne QH40A crystal heater problem
on6ab
Hi, as stated before, a crystal, manufactured to be used at room temperature is not very well suited to put in an oven. Below you see a typical stability range of such a crystal. If you put this crystal in an oven at 40 degrees, you're trying to keep it stable at a non-stable temperature. Not exactly a smart thing to do. Crystals to put in a 40 degrees oven are MADE for this, they will show the flat part of the curve at 40 degrees, not at 20 degrees. Op wo 5 jan. 2022 om 17:47 schreef k9wkj <k9wkjham@...>:
|
Re: Kuhne QH40A crystal heater problem
i made the sleeping bag for both of my 847s
keeps the swing down to pretty low numbers I made a homebrew crystal heater for my TEN-TEC 526 out of a little metal clip and a 40C Positive Temperature Coefficient Thermistor Amphenol #?YQS5745PTO? ?it has a 3C temp swing around 43C just did not find that necessary on the 847 maybe if one was driving a transverter it might require more help |
Re: S9 noise on HF with or without antenna
开云体育Hi Bill and thanks for the reply. I had a little nose inside and injected a smallish signal and found that there was stray RF on the IF from the G4HUP PAT board I fitted many years ago.?? I feel a bit silly now as the PAT board has worked flawlessly but for some reason I was getting some IMD and broadcast FM from the 3m band. I really love my FT847 and I have a spare (A2 US Import and C2 UK specifications) and I really don’t want to see them damaged. So I’ve taken out both PAT board (IF tap and 2nd receiver) and they are now in the trash. The main problem is the IF was being overloaded even though I was using the 2nd receiver PAT board and not the IF tap for Panadapter. ? Thanks for the heads up but this is resolved and I doubt I will be re-visiting the PAN adapter anytime soon. De Spence M0STO? Sent while portable! please excuse typos. On 5 Jan 2022, at 12:29, Bill <k2wh@...> wrote:
|
Re: S9 noise on HF with or without antenna
开云体育Not sure of the FT847, but does it have a function or ability to turn off the AGC ? ? From: [email protected] [mailto:[email protected]] On Behalf Of Spence M0STO via groups.io ? Dear Group, I have a bit of a strange question. My FT847 has nothing but S9 of noise on HF (I work mostly satellite these days so only just noticed it). I tried all bands but seem to be blighted with an S9 signal with or without the antenna connected. The other issue is when I tune to a strong AM station in the lower broadcast band 2.2mhz seemed to be the strongest +50db on AM but the audio is dreadful and sounds splattered, clipped and inaudiable. I have been using a passive loop on HF and I’m fearing DC or a strong signal has landed in the front end and done damage.? -- Bill, K2WH |
S9 noise on HF with or without antenna
Dear Group, I have a bit of a strange question. My FT847 has nothing but S9 of noise on HF (I work mostly satellite these days so only just noticed it). I tried all bands but seem to be blighted with an S9 signal with or without the antenna connected. The other issue is when I tune to a strong AM station in the lower broadcast band 2.2mhz seemed to be the strongest +50db on AM but the audio is dreadful and sounds splattered, clipped and inaudiable. I have been using a passive loop on HF and I’m fearing DC or a strong signal has landed in the front end and done damage.?
Before I tear my radio apart to resolve this I wondered if anyone had pointers. I know the FT897 used to suffer with S9 all the time due to the 455khz ceramic filters going bad but don’t think the FT847 uses them. ? Any help would be really appreciated. thanks in advanced, de Spence M0STO? see below the test gear on hand to resolve this. test gear: Marconi 2955 radio test set Marconi 2022 Signal Generator Rigol DSA1030A spectrum analyser Phillips 3833 60mhz Scope AF generator? VVM logic probe etc. GDO |
Re: Dodgy Rotary switch
Howdo Rob.? Spraying cleaner at it will do absolutely nothing. It is a crimped together unit, and no chance of getting any spray on to the contacts. I have new ones in stock, but usually clean the old ones. This involves the front off, knobs off, encoder out and put back together. I have done quite a few.? Regards old chap Andy~ G4XNG On Tue, 4 Jan 2022 at 20:09, Omni <selcor@...> wrote:
|
Re: Dodgy Rotary switch
开云体育Mechanical encoders get dirty just like Pots do. ?There is no problem with using a good quality cleaner that is intended for the purposes.? I would pick one that has some lubricating quality to it.? That will minimize the contact wear.? Caig Laboratories makes great products.? I use various concentrations of their Deoxit cleaner depending on what needs to be cleaned and how dirty it is.? I also use GC Electronics DE-OX-ID, which does a good job and is much less expensive than the Caig cleaners. ?I have been using both types for years with great results.? Just remember to use them sparingly.? You can always add more if needed.? Spray a little and work the encoder to see where you are.? It may take a little time and a couple of small squirts to get the results you want. ? From: [email protected] [mailto:[email protected]] On Behalf Of Rob ? Hi All, |
Re: Replacement parts needed.
They make parts that will not stick to epoxy because most people do not usually try. I would have drilled the inner out and used a bit of wire or a tiny diameter screwthread as a dowel before trying to glue, to give a better mechanical bond. On Tue, 28 Dec 2021 at 02:05, Bradley RIsk <riskbr@...> wrote:
|
Re: Replacement parts needed.
Bradley RIsk
开云体育The repair failed. What do they make those shafts out of that won’t stick to epoxy, CA, or fuse with solvent??? Sheesh. ? So I need both parts. ? Brad ? From: [email protected] <[email protected]>
On Behalf Of Andy Bosworth
Sent: Monday, December 27, 2021 3:33 PM To: [email protected] Subject: Re: [YaesuFT847] Replacement parts needed. ? I have the MEM/VFO encoder in stock.? ? ? On Mon, 27 Dec 2021 at 20:18, John Hopkinson via <hopkinsonj=[email protected]> wrote:
|
Re: Replacement parts needed.
I have the MEM/VFO encoder in stock.? Which is the one that you think you can repair? On Mon, 27 Dec 2021 at 20:18, John Hopkinson via <hopkinsonj=[email protected]> wrote:
|
Re: Replacement parts needed.
开云体育Hi try searching for Q9000704, I bought one from eBay last year for ?10 ukOn 27 Dec 2021, at 09:18, Bradley RIsk <riskbr@...> wrote:
|
Re: Replacement parts needed.
Bradley RIsk
开云体育Thanks for the info!! ? 73 Brad, N7IVV ? From: [email protected] <[email protected]>
On Behalf Of Nils Ostman
Sent: Monday, December 27, 2021 5:23 AM To: [email protected] Subject: Re: [YaesuFT847] Replacement parts needed. ? Hi, |
Replacement parts needed.
Bradley RIsk
Greetings.
I need to replace the components (encoders?) for the SUB-TUNE and MEM/VFO CH controls on my rig. It got dropped and the shafts broke off. I MIGHT be able to glue/epoxy one of the shafts together, but the other is irreparable. The PC board IDs are S6531 and S6538, but that's the best I can do for identification. Any hints on what parts I might search on at DigiKey or Mouser or whatever would be appreciated. 73 Brad, N7IVV |
Re: Need Guide to Use FT-847 For Digital Modes
开云体育Hi MikeI use a ZLP electronics digimaster pro as an interface between my FT847 and pc. It works seamlessly with HRD & Fldigi using PSK, Olivia etc, and although I am not in favour of FT 8 and other similar modes it works and allows full alc control from the front.? Hope this helps John M1FFQ On 22 Dec 2021, at 00:42, Micky Corrow <opus@...> wrote:
|