开云体育

Sorry I haven't followed up on some of your questions pertaining to my 817 which I received from Japan . I left off where I had reset a couple of the hf parameters in order to measure maximum power capability .

I then ,at that point decided to leave the rig at 6 watts output . Since that time I received low audio reports (too much dynamic range ) , I immediately suspected that by changing the power settings that the alc was affected . I then attempted to increased the ssb tx audio in the user menu settings , its default value was 50 , at 64 I became aware of a problem , the rig had no tx audio at 64(maximum value for this setting is 100 ) . Since the electronic level control that is used to attenuate mike level is a serial input device I assumed that Yaesu had a software bug , however since there was a lack of mike gain available to develop sufficient alc at 6 watts to make the audio punchy (remember : this radio relys heavily on alc for a full envelope as there is no DSP or pre-processing, it has no other form of processing but alc) I then , having taken note of the original values in the alignment menu , reset the 817 to the factory values . I continued to receive "thin" audio reports (too much dynamic range ) .

The audio could not be turned up high enough due to this "software bug" and the only way that I could develop the alc level required for communications audio was to "mouth " the mike and speak a little louder than normal (this becomes a problem with 3 kids sleeping ) . I contacted Mike at Yaesu and informed him about the bug and that the radio could never reach full tx mike gain . A few days later he received positive confirmation from Japan that there is an audio bug and Yaesu feels that it will not hinder the performance of the radio and that they will market in North America with this bug.

I disagree with their statement completely as I have hands on experience with the rig and it does not modulate sufficiently nor develop adaquate alc unless I speak close and loud .

The characteristic of the bug is as follows ,when one turns up the mike gain (ssb mike gain) past 64 the gain begins again from 0 (zero) and increments up 36 counts to digit 100 , if you compare the gain setting (with a scope) of 100 to a setting of 36 you will see that both levels are the same . I proposed an intermediate fix so that I wouldn't have to disturb my family and that is to change some resistor values on the 1st speech amp to increase the gain by approximately 6 db . I don't believe that Yaesu will impliment this change and the radio will be released with this bug as they have stated.

Aside from this I still love the radio and hope that Yaesu fixes their firmware quickly so that I can purchase a second one . I am currently working in Washington DC for the week and have worked DX ( Moscow) and some local US stations on 20 meters simply with a long wire dangling out the window of the hotel from the 8th floor . I really love the radio , just wish Yaesu would correct the problem before releasing the first version , Without opening the rig I will endevour to find a suitable replacement mike .

Just one last comment the mike gain works properly on FM and AM only ssb mike gain is affected by this bug .

73's Howard VE2AED

LAte breaking news , I arrived back in Montreal last evening from DC and connected my 817 to my 12 volt supply , went on 20 and suddenly had plumes of smoke from my 817 and then the radio was of course dead . Something in the rig had shorted out the batteries and caused a meltdown of the battery holder , fortunately the springs on the battery holder became annealed and opened up the battery circuit , had that not happened I would have probably had a fire in the radio as I am using 1.6 amp AA nicads . I immediately opened up the radio , removed the battery holder and measured 0 ohms from + to ground , same on the external DC input . I decided I ad had enough for one day since I had been out of town all week and brought the schematic to kids swimming lessons this morning . After tracing all paths only thing I could come up with was that the torroidal rf power line choke had probably shorted . When I returned home I immediately removed completely the main PCB , removed the choke and voila it was in fact shorted . I then stripped the torroid core of its 6 turns of no. 24 wire and rewound it with a higher temp enamal insulation then the original one , I think Yaesu overlooked this part of the circuit as after careful checking I observed that the melting temp of the original enamal on this choke (T35) had a very low melting temperature and to top it off there is no fuse what so ever between the internal batteries and the radio or for that matter the external connector and the radio , If this choke fails you have a disaster . I have taken a photo of the old wire and the newly installed choke and will post it tomorrow if I can find some time . I must say that removing the main PCB was very simple and I was impressed with the layout and the aluminum frame construction which is the TX heatsink as well , the rig is extremely easy to service in my opinion . I still like it very much and in no way am I trying to influence anyone here as to what choice to make , I am being purely objective and factual . The receiver sounds great and for those of you that asked there is no DSP in this radio , If in fact there were I wouldn't be so demanding about the mike gain bug which you will all probably see on the first run .

I did try an electret mike with higher output and it compensated for the lack of gain , problem was that it was originally meant for a vhf HT and had a poor shield which would cause rf feedback when I used an antenna close to the rig .

Hope this letter has been of interest to all of you .

73's
Howard VE2AED

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Howard,

Do you think your modifications and tests of the radio at 10 watts,
then running it at 6 watts output as opposed to (what I assume is)
the 4 watt design spec, had anything at all to due with the
'meltdown?"

73 =paul= w8kc

LAte breaking news , I arrived back in Montreal last evening from

DC and

connected my 817 to my 12 volt supply , went on 20 and suddenly had

plumes

of smoke from my 817 and then the radio was of course dead .

Something in

the rig had shorted out the batteries and caused a meltdown of the

battery

holder , fortunately the springs on the battery holder became

annealed and

opened up the battery circuit , had that not happened I would have

probably

had a fire in the radio as I am using 1.6 amp AA nicads . I

immediately

opened up the radio , removed the battery holder and measured 0

ohms from +

to ground , same on the external DC input . I decided I ad had

enough for

one day since I had been out of town all week and brought the

schematic to

kids swimming lessons this morning . After tracing all paths only

thing I

could come up with was that the torroidal rf power line choke had

probably

shorted . When I returned home I immediately removed completely the

main PCB

, removed the choke and voila it was in fact shorted . I then

stripped the

torroid core of its 6 turns of no. 24 wire and rewound it with a

higher temp

enamal insulation then the original one , I think Yaesu overlooked

this part

of the circuit as after careful checking I observed that the

melting temp of

the original enamal on this choke (T35) had a very low melting

temperature

and to top it off there is no fuse what so ever between the

internal

batteries and the radio or for that matter the external connector

and the

radio , If this choke fails you have a disaster . I have taken a

photo of

the old wire and the newly installed choke and will post it

tomorrow if I

can find some time . I must say that removing the main PCB was very

simple

and I was impressed with the layout and the aluminum frame

construction

which is the TX heatsink as well , the rig is extremely easy to

service in

my opinion . I still like it very much and in no way am I trying to
influence anyone here as to what choice to make , I am being purely
objective and factual . The receiver sounds great and for those of

you that

asked there is no DSP in this radio , If in fact there were I

wouldn't be so

demanding about the mike gain bug which you will all probably see

on the

first run .

I did try an electret mike with higher output and it compensated

for the

lack of gain , problem was that it was originally meant for a vhf

HT and had

a poor shield which would cause rf feedback when I used an antenna

close to

the rig .

Hope this letter has been of interest to all of you .

73's
Howard VE2AED

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Hi Howard -

This may not be a software bug. You may actually be getting all the gain
you can get.

You see, 64 hex is 100. I suspect that you have not a bug per se, but
one of representation. When one has the gain set to 50, could it not
really be 80 if it was being converted properly?

If I am correct, somewhere in there is (for example) 8A, 8B and so on,
which I don't think would display, but '80' may not increment beyond 89
for 5 or 6 ticks and then '90' would appear.

I've been caught on this a few times in software development when what I
thought was decimal display turned out in fact to be hex.

Just a thought...




Wayne
VE3EFJ

when checking the FM mike gain (the only difference is that it comes out of a different port of the electronic attenuator (this attenuator has unity gain ) the output level is higher . This is a bug I have an email acknowledgement from Yaesu . You will see when you receive yours that if you want the alc to move up scale at all you will have to eat the mike.



73's Howard

From: Wayne Montague/Ann Beattie <beemoe@...>
To: FT817@..., howardzz@...
Subject: Re: [FT817] Update on my 817
Date: Sun, 22 Oct 2000 10:36:14 -0400


Hi Howard -

This may not be a software bug. You may actually be getting all the gain
you can get.

You see, 64 hex is 100. I suspect that you have not a bug per se, but
one of representation. When one has the gain set to 50, could it not
really be 80 if it was being converted properly?

If I am correct, somewhere in there is (for example) 8A, 8B and so on,
which I don't think would display, but '80' may not increment beyond 89
for 5 or 6 ticks and then '90' would appear.

I've been caught on this a few times in software development when what I
thought was decimal display turned out in fact to be hex.

Just a thought...




Wayne
VE3EFJ

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Howard,
Thanks for the update. Sorry to hear that your 817 smoked.
I hate to tell you, but the 6 turns on a torroid core will measure a
dead short at DC. I'm sure that is not your problem.
Good luck
Mike M. KU4QO

Howard Z wrote:

In case I wasn't clear the original choke consisted of two parallel 6
turn windings on a torroid one of the windings connects to + battery
and the other to battery - and then to the ext connector . These
windings shorted together with no visible signs of a short , the
battery case took the load , spring connectors and all . The radio is
now perfect again , my hunch was correct only because after studying
the diagram it was the only zero ohm path that could have been
possible , every other circuit on the battery line has a resistor of
a value greater than 47 ohms and the US 13 volt (unswitched) line was
disconnected from the outside world . I plan to fuse the internal
battery with a low voltage fuse (low resistance ) as I don't want any
considerable voltage drop . I hope Yaesu does this too to avoid a
disaster , like someones luggage catching fire ---


In FT817@..., mikemo@a... wrote:

Howard,
Thanks for the update. Sorry to hear that your 817 smoked.
I hate to tell you, but the 6 turns on a torroid core will measure a
dead short at DC. I'm sure that is not your problem.
Good luck
Mike M. KU4QO

Howard Z wrote:

Sorry I haven't followed up on some of your questions pertaining

to my 817

which I received from Japan . I left off where I had reset a

couple of the

hf parameters in order to measure maximum power capability .

I then ,at that point decided to leave the rig at 6 watts

output . Since

that time I received low audio reports (too much dynamic

range ) , I

immediately suspected that by changing the power settings that

the alc was

affected . I then attempted to increased the ssb tx audio in the

user menu

settings , its default value was 50 , at 64 I became aware of a

problem ,

the rig had no tx audio at 64(maximum value for this setting is

100 ) .

Since the electronic level control that is used to attenuate mike

level is a

serial input device I assumed that Yaesu had a software bug ,

however since

there was a lack of mike gain available to develop sufficient alc

at 6 watts

to make the audio punchy (remember : this radio relys heavily on

alc for a

full envelope as there is no DSP or pre-processing, it has no

other form of

processing but alc) I then , having taken note of the original

values in the

alignment menu , reset the 817 to the factory values . I

continued to

receive "thin" audio reports (too much dynamic range ) .

The audio could not be turned up high enough due to

this "software bug" and

the only way that I could develop the alc level required for

communications

audio was to "mouth " the mike and speak a little louder than

normal (this

becomes a problem with 3 kids sleeping ) . I contacted Mike at

Yaesu and

informed him about the bug and that the radio could never reach

full tx mike

gain . A few days later he received positive confirmation from

Japan that

there is an audio bug and Yaesu feels that it will not hinder the
performance of the radio and that they will market in North

America with

this bug.

I disagree with their statement completely as I have hands on

experience

with the rig and it does not modulate sufficiently nor develop

adaquate alc

unless I speak close and loud .

The characteristic of the bug is as follows ,when one turns up

the mike gain

(ssb mike gain) past 64 the gain begins again from 0 (zero) and

increments

up 36 counts to digit 100 , if you compare the gain setting (with

a scope)

of 100 to a setting of 36 you will see that both levels are the

same . I

proposed an intermediate fix so that I wouldn't have to disturb

my family

and that is to change some resistor values on the 1st speech amp

to increase

the gain by approximately 6 db . I don't believe that Yaesu will

impliment

this change and the radio will be released with this bug as they

have

stated.

Aside from this I still love the radio and hope that Yaesu fixes

their

firmware quickly so that I can purchase a second one . I am

currently

working in Washington DC for the week and have worked DX (

Moscow) and some

local US stations on 20 meters simply with a long wire dangling

out the

window of the hotel from the 8th floor . I really love the

radio , just wish

Yaesu would correct the problem before releasing the first

version , Without

opening the rig I will endevour to find a suitable replacement

mike .

Just one last comment the mike gain works properly on FM and AM

only ssb

mike gain is affected by this bug .

73's Howard VE2AED

LAte breaking news , I arrived back in Montreal last evening from

DC and

connected my 817 to my 12 volt supply , went on 20 and suddenly

had plumes

of smoke from my 817 and then the radio was of course dead .

Something in

the rig had shorted out the batteries and caused a meltdown of

the battery

holder , fortunately the springs on the battery holder became

annealed and

opened up the battery circuit , had that not happened I would

have probably

had a fire in the radio as I am using 1.6 amp AA nicads . I

immediately

opened up the radio , removed the battery holder and measured 0

ohms from +

to ground , same on the external DC input . I decided I ad had

enough for

one day since I had been out of town all week and brought the

schematic to

kids swimming lessons this morning . After tracing all paths only

thing I

could come up with was that the torroidal rf power line choke had

probably

shorted . When I returned home I immediately removed completely

the main PCB

, removed the choke and voila it was in fact shorted . I then

stripped the

torroid core of its 6 turns of no. 24 wire and rewound it with a

higher temp

enamal insulation then the original one , I think Yaesu

overlooked this part

of the circuit as after careful checking I observed that the

melting temp of

the original enamal on this choke (T35) had a very low melting

temperature

and to top it off there is no fuse what so ever between the

internal

batteries and the radio or for that matter the external connector

and the

radio , If this choke fails you have a disaster . I have taken a

photo of

the old wire and the newly installed choke and will post it

tomorrow if I

can find some time . I must say that removing the main PCB was

very simple

and I was impressed with the layout and the aluminum frame

construction

which is the TX heatsink as well , the rig is extremely easy to

service in

my opinion . I still like it very much and in no way am I trying

to

influence anyone here as to what choice to make , I am being

purely

objective and factual . The receiver sounds great and for those

of you that

asked there is no DSP in this radio , If in fact there were I

wouldn't be so

demanding about the mike gain bug which you will all probably see

on the

first run .

I did try an electret mike with higher output and it compensated

for the

lack of gain , problem was that it was originally meant for a vhf

HT and had

a poor shield which would cause rf feedback when I used an

antenna close to

the rig .

Hope this letter has been of interest to all of you .

73's
Howard VE2AED

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