Re: Small lamp reference for Drake L7
And I would highly recommend choosing the ones with insulated leads. Spend the extra money.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Thu, Jan 2, 2025 at 22:07, Jim Shorney via groups.io < jimNU0C@...> wrote:
The SSB lamp is a NE-2H neon. The rest are generic instrument lamps. Probably 24V since they run from 22VAC with a 150 Ohm series resistor. You might want to measure the AC voltage across one that is lit. They can be found with or without the long insulated wire leads.
On Thu, 02 Jan 2025 12:47:24 -0800
"Mohamed VA2MKX via groups.io" <va2mkx@...> wrote:
> Hello,
>
> I am? looking for the part reference for the very small lamps used to display the buttons pushed state (Ep, Ig, STBY, OPR, ...).
--
73
-Jim
NU0C
|
Re: T-4XC has a "condition"
Dean....you wrote....
OK guys, ? Here is an observation. I just cleaned the power connection and decided to check the bias again. All knobs turned to “0”. Now, on the RF tune I see a “0” in the 10 meter section. At this point I can get the bias to the tick mark. Now I see another “0” in the 160 meter range. The lowest bias setting here is .3 amps ? With the bias set now the tune procedure is closer to what I see on videos and I get a grid dip. But for normal operation all knobs are fully CW. ? Dean
Sorry but I am losing you here with some of your statements about the "zero" you are getting at 10m and 160.? What "zero" are you talking about?
Start on 40m. Mode switch in SSB position. Band switch?set on 40m.? Plate Tune about 10 o'clock....Load about 10 o'clock.? RF Tune set at 40m.? RF wattmeter in line on the transmitter output to a 50 ohm dummy load.? GAIN Control set?AT ZERO - all the way counter-clockwise!!!!!!
Key up the T-4XC with a microphone?PTT? and no audio.....OR put the Mode switch into TUNE.? ?Adjust?the bias pot on AC-4 power supply to set at 70 ma (the tick mark) on the T-4XC plate current meter.
If that goes OK, then switch the MODE switch to TUNE and increase the GAIN control until you see the meter rise slightly, then peak that reading with the RF Tune control.? You should see some output on the wattmeter. Quickly peak the PLATE control for maximum output, which should correspond pretty closely to a dip in the PLATE CURRENT.? Increase the load control from the 10 o'clock position slightly, and increase?GAIN slightly, then dip the Plate Current again to a minimum with the PLATE control. Increase the GAIN control again and do all that once more.? Keep that process?up until you have about 250-300mA Plate current when the Plate control is dipped and output is at about 120w or so.? Keep the transmissions?short...allow cooling time if needed...which is likely as a beginner.? This whole process becomes much quicker with practice!
You will find that the LOAD control needs to be at around 10 o'clock?for 80/40m and maybe 12 to 2 o'clock for the higher bands when all tuned up. Same (+/-) for the PLATE control.
At no time should you see Plate?Current pin to the right!? If so...something is wrong.? Mistuned...gain too high...bad output cable or load etc.
Good luck!? Hope I've spelled this out correctly.? Doing it from memory.? Others are welcome to chime in!
73 Peter VE7PS
73 Peter VE7PS
OK guys,
?
Here is an observation. I just cleaned the power connection and decided to check the bias again. All knobs turned to “0”. Now, on the RF tune I see a “0” in the 10 meter section.
At this point I can get the bias to the tick mark. Now I see another “0” in the 160 meter range. The lowest bias setting here is .3 amps
?
With the bias set now the tune procedure is closer to what I see on videos and I get a grid dip. But for normal operation all knobs are fully CW.
?
Dean
?
?
Barry...indeed, check for correct idling current with zero
drive. Adjust it using the bias control on the AC-4 power supply.? You are aiming for about 70 mA (the "tick mark").
Also.....practice tuning up into a known good 50 Ohm load rated at 150w or better with known good cables first.?
Dump the "tuner" for now.? I would put a wattmeter inline to the 50 ohm load if you have one,?rather than trying to use the internal relative output meter.? That way there are fewer buttons to "mess" with until you are comfortable with the tune-up process.
And if you are pinning the ammeter...STOP right away, as something is wrong!? Back off the drive and try again.
?
How have you set your bias. That’s the first step. Pinned to the right is not a condition you want to be in for long so I would suggest not tuning up until you figure it out.? I would verify
that you have appropriate and steady bias current first.
On Thursday, January 2, 2025 at 10:01:40 AM CST, Dean N2TNN via
<n2tnn=[email protected]> wrote:
I have a T-4XC in great condition but is not acting normal. It puts out 110 watts, sounds great on CW and cooperates with my straight key. Unknown about the
SSB side because I never used it.
This is difficult to express because I don't really know what I am talking about so here goes. Tuning the rig on different bands takes forever to get it right.
I have watched videos and it looks easy. I follow the instructions in the manual and it never is the same.
All controls are set CCW. I then turn up the gain control slowly, maybe 1/4 the way and the needle pins to the right. Once it is pinned I can never get it to
dip when I adjust the plate knob.
So what I do next is to fool with the controls to get max power out with the lowest SWR on the tuner. With the load knob adjusted for output the needle is still
pinned. When I push it in the needle moves down to about .300
Also, after tuning up with the "tune" setting I go to CW and when I key down I have to fine tune all the settings again.
I really like this rig and want to use it but something is not right. Any suggestions?
|
I've seen instruction manuals where you adjust the AF gain to a 'comfortable' level and use the RF gain as a volume knob.?
I learned to operate this way in my early days and, as I understand, it helps keep the RF noise out-of-the-radio!
?
--
TNX-n-73's fer now....
KF6JS - Tony
|
Re: Small lamp reference for Drake L7
The SSB lamp is a NE-2H neon. The rest are generic instrument lamps. Probably 24V since they run from 22VAC with a 150 Ohm series resistor. You might want to measure the AC voltage across one that is lit. They can be found with or without the long insulated wire leads. On Thu, 02 Jan 2025 12:47:24 -0800 "Mohamed VA2MKX via groups.io" <va2mkx@...> wrote: Hello,
I am? looking for the part reference for the very small lamps used to display the buttons pushed state (Ep, Ig, STBY, OPR, ...). -- 73 -Jim NU0C
|
In the commercial 2-way radio business this was a feature, not a bug. Kept the dispatcher from turning the volume all the way down either accidentally or on purpose. On Thu, 2 Jan 2025 15:48:10 -0600 "Gary Follett via groups.io" <xntrick1948@...> wrote: Later TR7’s did not suffer this problem. It seems the pot was changed to one which got to zero ohms before the click.
Gary
W0DVN
On Jan 2, 2025, at 3:44?PM, Rob Sherwood via groups.io <rob@...> wrote:
The R-4C has the same problem. It may go clear back to my original R-4. Rob, NC0B
-----Original Message-----
From: [email protected] <mailto:[email protected]> [mailto:[email protected]] On Behalf Of jerry-KF6VB
Sent: Thursday, January 02, 2025 11:15 AM
To: [email protected] <mailto:[email protected]>
Cc: Jim Shorney via groups.io <>
Subject: [DRAKE-RADIO] TR7 Audio
One minor audio annoyance with the TR7 - the volume control doesn't go
all the way to zero.
Instead of a tradition voltage divider pot, they do something with the
AGC. So to get
the thing to quiet down, I also turn down the RF gain.
- Jerry, KF6VB -- 73 -Jim NU0C
|
Re: R4C Sherwood audio mod questions
Hi Rob,
?
Thank you for posting these six files.
?
Chuck
|
Re: T-4XC Sideband adjustments?
BTW, the one with the long shaft is for balancing the carrier, along with the 10-turn pot.? These three adjustments are in the same patch of real estate.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:50 PM, Steve Wedge, W1ES <w1es@...> wrote:
the one with the slot.? If you are on frequency, you may have a bad crystal filter.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:47 PM, Ed KG5UN via groups.io <maikranze@...> wrote:
Carrier oscillator is on freq. Sorry but I still dont know where C-6 is. Is it the big silver looking thing with a slot for a screw driver or the taller looking thing against the back of the chassis with the slug sticking out of it?
On Thu, Jan 2, 2025 at 4:41?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Check that your carrier oscillator is at 5645 kHz. C6 is the ceramic trimmer on top of the chassis, right-rear corner area.
If your CO is on-frequency, you could have a bad filter. Rare, but it happens.
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:09 PM, Ed KG5UN via <maikranze= [email protected]> wrote:
My T-4XC sounds decent on LSB but very tinny and pinched on USB. How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it?
Thanks, Ed KG5UN
|
Re: T-4XC Sideband adjustments?
I turn it and it just spins and spins. doesnt?seem to change anything. Ed
On Thu, Jan 2, 2025 at 4:50?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: the one with the slot.? If you are on frequency, you may have a bad crystal filter.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:47 PM, Ed KG5UN via <maikranze= [email protected]> wrote:
Carrier oscillator is on freq. Sorry but I still dont know where C-6 is. Is it the big silver looking thing with a slot for a screw driver or the taller looking thing against the back of the chassis with the slug sticking out of it?
On Thu, Jan 2, 2025 at 4:41?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Check that your carrier oscillator is at 5645 kHz. C6 is the ceramic trimmer on top of the chassis, right-rear corner area.
If your CO is on-frequency, you could have a bad filter. Rare, but it happens.
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:09 PM, Ed KG5UN via <maikranze= [email protected]> wrote:
My T-4XC sounds decent on LSB but very tinny and pinched on USB. How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it?
Thanks, Ed KG5UN
|
Re: T-4XC Sideband adjustments?
the one with the slot.? If you are on frequency, you may have a bad crystal filter.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:47 PM, Ed KG5UN via groups.io <maikranze@...> wrote:
Carrier oscillator is on freq. Sorry but I still dont know where C-6 is. Is it the big silver looking thing with a slot for a screw driver or the taller looking thing against the back of the chassis with the slug sticking out of it?
On Thu, Jan 2, 2025 at 4:41?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Check that your carrier oscillator is at 5645 kHz. C6 is the ceramic trimmer on top of the chassis, right-rear corner area.
If your CO is on-frequency, you could have a bad filter. Rare, but it happens.
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:09 PM, Ed KG5UN via <maikranze= [email protected]> wrote:
My T-4XC sounds decent on LSB but very tinny and pinched on USB. How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it?
Thanks, Ed KG5UN
|
Re: T-4XC Sideband adjustments?
Carrier oscillator is on freq. Sorry but I still dont?know where C-6 is. Is it the big silver looking thing with a slot for a screw driver?or the taller looking thing against the back of the chassis?with the slug sticking out of it?
On Thu, Jan 2, 2025 at 4:41?PM Steve Wedge, W1ES/4 via <w1es= [email protected]> wrote: Check that your carrier oscillator is at 5645 kHz.? C6 is the ceramic trimmer on top of the chassis, right-rear corner area.
If your CO is on-frequency, you could have a bad filter.? Rare, but it happens.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:09 PM, Ed KG5UN via <maikranze= [email protected]> wrote:
My T-4XC sounds decent on LSB but very tinny and pinched on USB. How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it?
Thanks, Ed KG5UN
|
Re: T-4XC has a "condition"
OK guys,
?
Here is an observation. I just cleaned the power connection and decided to check the bias again. All knobs turned to “0”. Now, on the RF tune I see a “0” in the 10 meter section.
At this point I can get the bias to the tick mark. Now I see another “0” in the 160 meter range. The lowest bias setting here is .3 amps
?
With the bias set now the tune procedure is closer to what I see on videos and I get a grid dip. But for normal operation all knobs are fully CW.
?
Dean
?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]>
On Behalf Of VE7PS via groups.io
Sent: Thursday, January 2, 2025 1:06 PM
To: [email protected]
Subject: Re: [DRAKE-RADIO] T-4XC has a "condition"
?
Barry...indeed, check for correct idling current with zero
drive. Adjust it using the bias control on the AC-4 power supply.? You are aiming for about 70 mA (the "tick mark").
Also.....practice tuning up into a known good 50 Ohm load rated at 150w or better with known good cables first.?
Dump the "tuner" for now.? I would put a wattmeter inline to the 50 ohm load if you have one,?rather than trying to use the internal relative output meter.? That way there are fewer buttons to "mess" with until you are comfortable with the tune-up process.
And if you are pinning the ammeter...STOP right away, as something is wrong!? Back off the drive and try again.
?
How have you set your bias. That’s the first step. Pinned to the right is not a condition you want to be in for long so I would suggest not tuning up until you figure it out.? I would verify
that you have appropriate and steady bias current first.
On Thursday, January 2, 2025 at 10:01:40 AM CST, Dean N2TNN via
<n2tnn=[email protected]> wrote:
I have a T-4XC in great condition but is not acting normal. It puts out 110 watts, sounds great on CW and cooperates with my straight key. Unknown about the
SSB side because I never used it.
This is difficult to express because I don't really know what I am talking about so here goes. Tuning the rig on different bands takes forever to get it right.
I have watched videos and it looks easy. I follow the instructions in the manual and it never is the same.
All controls are set CCW. I then turn up the gain control slowly, maybe 1/4 the way and the needle pins to the right. Once it is pinned I can never get it to
dip when I adjust the plate knob.
So what I do next is to fool with the controls to get max power out with the lowest SWR on the tuner. With the load knob adjusted for output the needle is still
pinned. When I push it in the needle moves down to about .300
Also, after tuning up with the "tune" setting I go to CW and when I key down I have to fine tune all the settings again.
I really like this rig and want to use it but something is not right. Any suggestions?
|
Re: Replacing T4XC Finals?
Film resistors will work fine. Use the same coils.
The final tubes should be 6JB6's
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 3:30 PM, Jay W6CJ via groups.io <lastradioman@...> wrote:
I looked into the PA I damaged when a faulty key put the radio in transmit: - One of the parasitic choke leads popped out of the resistor.
- One of the 1-watt cathode resistors is cracked and both read higher than 15 ohms.
- No more than 75mA when tuning.
I'm thinking of replacing the 6GE5s; both cathode resistors with 2-watt film resistors; both parasitic chokes; possibly replacing the 12BY7 driver tube.
Appreciate any expert advice on where else to check and what else to replace.
Thanks & 73 Jay W6CJ
|
Re: T-4XC Sideband adjustments?
Check that your carrier oscillator is at 5645 kHz.? C6 is the ceramic trimmer on top of the chassis, right-rear corner area.
If your CO is on-frequency, you could have a bad filter.? Rare, but it happens.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 5:09 PM, Ed KG5UN via groups.io <maikranze@...> wrote:
My T-4XC sounds decent on LSB but very tinny and pinched on USB. How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it?
Thanks, Ed KG5UN
|
My TR7A still has the annoying feature of not going to no signal.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Thursday, January 2nd, 2025 at 4:48 PM, Gary Follett via groups.io <xntrick1948@...> wrote:
Later TR7’s did not suffer this problem. It seems the pot was changed to one which got to zero ohms before the click.?
Gary
W0DVN On Jan 2, 2025, at 3:44?PM, Rob Sherwood via groups.io <rob@...> wrote:
The R-4C has the same problem. It may go clear back to my original R-4. ?Rob, NC0B-----Original Message-----From:?[email protected]?[mailto:[email protected]] On Behalf Of jerry-KF6VBSent: Thursday, January 02, 2025 11:15 AMTo:?[email protected]Cc: Jim Shorney via?Subject: [DRAKE-RADIO] TR7 AudioOne minor audio annoyance with the TR7 - the volume control doesn't go?all the way to zero.Instead of a tradition voltage divider pot, they do something with the?AGC. ?So to getthe thing to quiet down, I also turn down the RF gain.?????????????????- Jerry, KF6VBOn 2025-01-01 08:06, Jim Shorney via groups.io wrote:FWIW the TR7 uses an LM380. It works pretty well.
On Wed, 1 Jan 2025 10:45:24 -0500
"Mike Bryce via groups.io" <prosolar@...> wrote:
FYI… I designed an audio amp board for the R4C that used a LM380.?
Worked great and had plenty of humph to drive the MS4 speaker to room?
filling volume
--
73
-Jim
NU0C
|
Re: Replacing T4XC Finals?
Peter, Oops... I meant 6JB6A's.?? The NOS 6JB6A tubes I see for sale are never listed as "matched pair".... is that going to be a problem? Thanks for the screen resistor advice. 73 Jay W6CJ
Jay:
Couple of things....
Suspect you made an error about the final tubes.? 6GE5's wouldn't fit as they are 12 pin tubes, with the Plate on pin 7 instead of plate cap like the original tube, a 6JB6.? Perhaps you meant 6GJ5?? I believe some have used those in the T4X(any) transmitters.
It's not unusual to see the original cathode resistors up around 17-18 ohms by the time, and they still work fine, but seeing as you will be replacing the cracked one?I would do both for sure.? My "change 'em out" threshold?is usually about 17.2 ohms.
Check the screen resistors while you are in there as well. Again, common to see the original 68 ohm resistors drifted up around 75 ohms or thereabouts.? Higher than that and they get swapped out for new ones.
Good luck.
73 Peter VE7PS
I looked into the PA I damaged when a faulty key put the radio in transmit: - One of the parasitic choke leads popped out of the resistor.
- One of the 1-watt cathode resistors is cracked and both read higher than 15 ohms.
- No more than 75mA when tuning.
I'm thinking of replacing the 6GE5s; both cathode resistors with 2-watt film resistors; both parasitic chokes; possibly replacing the 12BY7 driver tube.
Appreciate any expert advice on where else to check and what else to replace.
Thanks & 73 Jay W6CJ
|
T-4XC Sideband adjustments?
My T-4XC sounds decent on LSB but very?tinny and pinched on USB.? How do I adjust this? I saw a reference to adjusting C-6 but I can not find a C-6. Where is it??
Thanks, Ed KG5UN
|
I don't actually know but suspect they are the same. Pillow stuffing would work OK and is likely cheaper. Anything sold for audio seems to become expensive.
toggle quoted message
Show quoted text
On 1/2/2025 1:56 PM, Stan Gammons via groups.io wrote: I've wondered if the Acousta-Stuf? Polyfil is the same as the Poly-Fil pillow stuffing one can buy at Walmart?
73
Stan
KM4HQE
--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998
|
I've wondered if the Acousta-Stuf? Polyfil is the same as the
Poly-Fil pillow stuffing one can buy at Walmart?
73
Stan
KM4HQE
On 1/2/25 13:52, Joe - W7RKN via
groups.io wrote:
toggle quoted message
Show quoted text
Yup…One
and the same, albeit a wee (sic)
bit cheaper at your store
Joe
– W7RKN
?
?
Is
this the same product?
|
Rob — I read somewhere that the last version of the SE-3, with the addition of the "AR" switch on the front panel, involved only the addition of the switch and a 100k resistor.? Can you please confirm that's correct and if so, explain where the 100k resistor
is connected?? ?
Thanks, and happy new year!
Regards,
Art Delibert, KB3FJO
|
Later TR7’s did not suffer this problem. It seems the pot was changed to one which got to zero ohms before the click.?
Gary
W0DVN
toggle quoted message
Show quoted text
On Jan 2, 2025, at 3:44?PM, Rob Sherwood via groups.io <rob@...> wrote:
The R-4C has the same problem. It may go clear back to my original R-4. ?Rob, NC0B-----Original Message-----From:?[email protected]?[mailto:[email protected]] On Behalf Of jerry-KF6VBSent: Thursday, January 02, 2025 11:15 AMTo:?[email protected]Cc: Jim Shorney via?Subject: [DRAKE-RADIO] TR7 AudioOne minor audio annoyance with the TR7 - the volume control doesn't go?all the way to zero.Instead of a tradition voltage divider pot, they do something with the?AGC. ?So to getthe thing to quiet down, I also turn down the RF gain.?????????????????- Jerry, KF6VBOn 2025-01-01 08:06, Jim Shorney via groups.io wrote:FWIW the TR7 uses an LM380. It works pretty well.
On Wed, 1 Jan 2025 10:45:24 -0500
"Mike Bryce via groups.io" <prosolar@...> wrote:
FYI… I designed an audio amp board for the R4C that used a LM380.?
Worked great and had plenty of humph to drive the MS4 speaker to room?
filling volume
--
73
-Jim
NU0C
|
Tony Yamin
Jim Shorney
Ed KG5UN
Jay W6CJ