yes the xtal/vfo switch is clean, in fact at one point I had it jumped out to make sure.? I was reading LO and PTO at V8 socket pins with a scope.? I? have hit the tube socket with contact cleaner. Yes the xtal switch was in Normal and I was seeing the correct LO frequency per band switch position.? Thanks for your reply Peter.
Ronald Brown 701.520.3478
-------- Original Message --------
Subject: Re: [DRAKE-RADIO] r4b revival
From: "VE7PS" < ve7ps@...>
Date: Mon, April 12, 2021 12:26 am
To: [email protected]
Ron: Curious exactly where you were checking for the PTO signal and the LO signal?? Those signals may not be getting to the cathode/grid of V-8 if the switch S-4 is in the wrong position ("VFO" is correct) or is dirty.? I realize you mentioned you had cleaned the switches, but this one, on the side of the receiver, isn't always obvious, and I have had trouble with these slide switches on many Drake rigs, especially the 4-line transceivers and the SC-2 rx converter. Also make sure the XTALS switch is in the NORM position and ensure it is clean as well. Keep us posted. 73 Peter VE7PS On 2021-04-11 8:17 p.m., Ron K0IDX wrote:
I have been working on this R4B for awhile now. recapped and cleaned all switches. I verified good LO and PTO signals to the premixer with an oScope.. However V8, the premixer, is not doing its thing. I have new , tested 6hs6's for both v2 and v8. Voltages check ok except for v8 pin6 which is 145vdc with d14 out of circuit or 108 with it in, normal would be 120. Resistance at pin 6 runs high at 18.6k instead of 12k. R50 is good at 22k.? The pin1 grid shows 0v. Plate p5 is 145v.? ?at pin7 v2 cathode I see a few mv of the LO frequency, not the desired LO - PTO frequency.? ?Have tried alignment paying attention to tuned circuits with T3 and T4, the trimmer caps associated with T3 are not responsive, neither do the trimmer caps at T4 make any difference. I verified the measurement of the slug positions on the preselector rack.? Complicating troubleshooting is the calibrator not working however v1 and trimmers are working with external sig generator.? 5595khz LO2 is good at v3 but I'm not that far yet.? Any input or next step direction would be greatly appreciated as I seem to have begun to go in circles with this. At my age thats not unusual..... ron?
|
Re: Where do you get an X-Lock from Now?
After 15 years of producing kits for the Amateur Radio enthusiast,?
Ron and Gill Taylor of Cumbria Designs (UK) ceased their business on 17th December 2018.
?
The Cambria Designs X-Lock was a popular product during this time.
Review at eHam.net
Roland Elmiger, HB9GAA founder of ELcon Engineering (Switzerland)
is now offering the universal ELcon EL-34, FLL-VFO Stabilizer.
A nice FLO-VFO Stabilizer replacement for the discontinued X-Lock.
¡ª
Universal FLL-VFO Stabilizer EL-34 (kit or assembled), 45.00 Swiss Francs.
?
ELcon EL-34
===
Good Luck.
greg, w9gb
|
John,
I am thankful that the oscillator is working now for all bands. ?You are welcome for any helpful suggestions. ?You have observed that sudden oscillation occurs when all conditions for oscillation are met, just as it should.
Concerning the crystal pins loose in their sockets, I assume the crystal holders are either HC-6/U or HC-48/U, same dimensions with both. ?In my 2-B, each crystal has both pins bent, very slightly toward each other to create a transition fit with the socket. ?The bend occurs at the holder insulated wall, as if someone gently pushed on the end of each pin toward the other, or used smooth-jaw pliers to make the bend. ?The offset from the perpendicular position measures 0.01 inches, using a Vernier caliper. ?The pin diameter measures 0.05 inches. ?Check your crystals. ?If you don¡¯t see this slight offset from perpendicular, bend each pin toward each other for a transition fit. ?My crystals plug into their socket smoothly, and quite snugly, all the way. ?I expect that the socket barrels flex from perpendicular, conforming to the offset in the pin, when the crystal is inserted, creating the secure transition fit.
73,
Michael Smith, N4KZO
|
Re: Where do you get an X-Lock from Now?
James,
? ? ? ? ? Check QTH.com.? There is a ham who advertises his version of a VFO stabilizer. I never bought one. I cannot say anything good or bad about it.?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Wayne/WC1C
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With Cumbria Designs seemingly gone sadly, does anyone know if there is anyone making a similar device as the X-Lock anywhere?
Kind Regards
James
MD0MDI
|
Where do you get an X-Lock from Now?
With Cumbria Designs seemingly gone sadly, does anyone know if there is anyone making a similar device as the X-Lock anywhere?
Kind Regards
James
MD0MDI
|
Ron:
Curious exactly where you were checking for the PTO signal and the
LO signal?? Those signals may not be getting to the cathode/grid of
V-8 if the switch S-4 is in the wrong position ("VFO" is correct) or
is dirty.? I realize you mentioned you had cleaned the switches, but
this one, on the side of the receiver, isn't always obvious, and I
have had trouble with these slide switches on many Drake rigs,
especially the 4-line transceivers and the SC-2 rx converter.
Also make sure the XTALS switch is in the NORM position and ensure
it is clean as well.
Keep us posted.
73
Peter
VE7PS
On 2021-04-11 8:17 p.m., Ron K0IDX
wrote:
toggle quoted message
Show quoted text
I have been working on this R4B for awhile now. recapped and
cleaned all switches. I verified good LO and PTO signals to the
premixer with an oScope.. However V8, the premixer, is not doing
its thing. I have new , tested 6hs6's for both v2 and v8. Voltages
check ok except for v8 pin6 which is 145vdc with d14 out of
circuit or 108 with it in, normal would be 120. Resistance at pin
6 runs high at 18.6k instead of 12k. R50 is good at 22k.? The pin1
grid shows 0v. Plate p5 is 145v.? ?at pin7 v2 cathode I see a few
mv of the LO frequency, not the desired LO - PTO frequency.? ?Have
tried alignment paying attention to tuned circuits with T3 and T4,
the trimmer caps associated with T3 are not responsive, neither do
the trimmer caps at T4 make any difference. I verified the
measurement of the slug positions on the preselector rack.?
Complicating troubleshooting is the calibrator not working however
v1 and trimmers are working with external sig generator.? 5595khz
LO2 is good at v3 but I'm not that far yet.? Any input or next
step direction would be greatly appreciated as I seem to have
begun to go in circles with this. At my age thats not unusual.....
ron?
|
I have been working on this R4B for awhile now. recapped and cleaned all switches. I verified good LO and PTO signals to the premixer with an oScope.. However V8, the premixer, is not doing its thing. I have new , tested 6hs6's for both v2 and v8. Voltages check ok except for v8 pin6 which is 145vdc with d14 out of circuit or 108 with it in, normal would be 120. Resistance at pin 6 runs high at 18.6k instead of 12k. R50 is good at 22k.? The pin1 grid shows 0v. Plate p5 is 145v.? ?at pin7 v2 cathode I see a few mv of the LO frequency, not the desired LO - PTO frequency.? ?Have tried alignment paying attention to tuned circuits with T3 and T4, the trimmer caps associated with T3 are not responsive, neither do the trimmer caps at T4 make any difference. I verified the measurement of the slug positions on the preselector rack.? Complicating troubleshooting is the calibrator not working however v1 and trimmers are working with external sig generator.? 5595khz LO2 is good at v3 but I'm not that far yet.? Any input or next step direction would be greatly appreciated as I seem to have begun to go in circles with this. At my age thats not unusual..... ron?
|
Like the others have said, the Drake NB was only designed for ignition noise for those that took these mobile.
I added a pre-wired BHI DSP noise reduction inside my MS-4 cabinet.? I hid the on/off and threshold buttons on the bottom so that it still looks entirely stock.? It is a bypass unit, and when switched off the normal Drake audio is passed directly through.? Engage the DSP, though, and it takes the noise reduction into the 21st century.? Highly recommended!
Eric
WK3B
|
I tried this on my R4B and found that while it worked it didn't make the NB any more effective on noise other than ignition noise. Ignition noise is rare these days, about the only time I hear it is from the gardener's mower. The threshold of the NB is such that it will prevent pulse noise from raising the AVC level, which is what is expected of it. Lowering the threshold much begins to produce distortion. There are more elaborate blankers that are more effective on power line noise but the best ones seem to be the digital processing ones that are external to the receiver.
?? The theory of the noise blanker is not as simple as it may appear. The idea is that the blanker will cut off the RF path during the pulse but the effect of the bandwidth on the noise wave form at both the sensing and control points is critical plus you don't want the blanker to cut off desired signals.
?? As a matter of comfort in listening a simple clipper on the audio may be helpful. While its best to have it on the input to the audio stage even a simple solid state diode clipper on the audio output may help with some types of power line noise. My experience with many old fashioned receivers with both series and shunt clippers is that they are at best illusory.
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On 4/11/2021 10:45 AM, Robert Berg via groups.io wrote:
David,
You can try a mod to permit an adjustment to the NB threshold, as per this suggestion: <>
This allows an adjustable threshold, as per the original R-4 configuration. Might help.
Bob
K7CY
On Apr 11, 2021, at 10:10 AM, AC9PA via groups.io <byroncordes@...> wrote:
?Don¡¯t expect miracles with the NB ! It works on some noise and some it just don¡¯t care! I would eliminate all noise in and around house first!
I run a Timewave dsp599 ( works on audio ) which makes the radio much better to listen to.
My R4C I don¡¯t have a NB in it the first IF is to narrow for stock NB to work but using the Timewave ?, lightning isnt to bad ?and I don¡¯t make any rf noise in house or if I do I can turn that light off Hihi
73s Byron AC9PA
On Apr 11, 2021, at 11:20 AM, wb6ogd <garywinblad@...> wrote:
?The Drake blanker is very effective... ?Like Richard says it works great on ignition noise.
Back in the day it made the difference between being able to hear a station or not.
Now a days, there isn't much ignition noise anymore so it really doesn't do much.
73,
Gary
WB6OGD
On 4/11/2021 7:36 AM, Richard Knoppow wrote:
??I can talk about the R4B. The blanker works fine on ignition noise, which was what it was mostly designed for but does nothing for the grinding line noise that is much more common. I tested it using a Tektronix pulse generator. It does work but is not like the blankers found in some more modern receivers. The idea of the blanker is to prevent pulse noise like ignition noise from causing the AVC to reduce sensitivity. It also does not affect the sort of noise a conventional noise limiter of the sort found in boatanchor receivers will take out but the usual series valve limiter does not work for CW or SSB. I think there are after market noise removers that work pretty well.
On 4/11/2021 5:09 AM, David Lipson via groups.io wrote:
Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David
N9pvf
--
Richard Knoppow
1oldlens1@...
WB6KBL
|
David,
You can try a mod to permit an adjustment to the NB threshold, as per this suggestion:?
This allows an adjustable threshold, as per the original R-4 configuration. Might help.
Bob
K7CY
toggle quoted message
Show quoted text
On Apr 11, 2021, at 10:10 AM, AC9PA via groups.io <byroncordes@...> wrote:
? Don¡¯t expect miracles with the NB ! It works on some noise and some it just don¡¯t care! I would eliminate all noise in and around house first! I run a Timewave dsp599 ( works on audio ) which makes the radio much better to listen to. My R4C I don¡¯t have a NB in it the first IF is to narrow for stock NB to work but using the Timewave ?, lightning isnt to bad ?and I don¡¯t make any rf noise in house or if I do I can turn that light off Hihi 73s Byron AC9PA On Apr 11, 2021, at 11:20 AM, wb6ogd <garywinblad@...> wrote:?The Drake blanker is very effective... ?Like Richard says it works great on ignition noise.Back in the day it made the difference between being able to hear a station or not.Now a days, there isn't much ignition noise anymore so it really doesn't do much.73,GaryWB6OGDOn 4/11/2021 7:36 AM, Richard Knoppow wrote: ??I can talk about the R4B. The blanker works fine on ignition noise, which was what it was mostly designed for but does nothing for the grinding line noise that is much more common. I tested it using a Tektronix pulse generator. It does work but is not like the blankers found in some more modern receivers. The idea of the blanker is to prevent pulse noise like ignition noise from causing the AVC to reduce sensitivity. It also does not affect the sort of noise a conventional noise limiter of the sort found in boatanchor receivers will take out but the usual series valve limiter does not work for CW or SSB. I think there are after market noise removers that work pretty well.
On 4/11/2021 5:09 AM, David Lipson via groups.io wrote:
Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David
N9pvf
|
What is needed are detailed specs on the radio before and after if TX use of the filter is planned. I don't see such information published anywhere. I am not saying that the filters are not good quality. I am sure they are. But in a world full of unintended consequences there is not enough information for the technical ham to make an informed decision. Dozens of eHam reviews and user testimonials that say "works great!" notwithstanding. 73 -Jim NU0C On Sun, 11 Apr 2021 17:23:38 +0000 "Tony Deprato" <tony.deprato@...> wrote: Myself and Dale W4OP of PAR Eng.check his restore work .have used Frank's filters.they work and work well. I have them in C lines and TR7 lines.Frank has Sweeps of all his filters on the website. Check them against the old Drake sweeps..73.Tony wa4jqs
Sent via the Samsung GALAXY S? 5, an AT&T 4G LTE smartphone
|
Myself and Dale W4OP? of PAR Eng.check his restore work .have used Frank's filters.they work and work well. I have them in C lines and TR7 lines.Frank has Sweeps of all his filters on the website. Check them against the old Drake sweeps..73.Tony wa4jqs?
Sent via the Samsung GALAXY S? 5, an AT&T 4G LTE smartphone
|
Exactly! 73 -Jim NU0C On Sun, 11 Apr 2021 09:18:19 -0700 "Jeff Herhold" <jrherhold@...> wrote: A final consideration, of course, is to ensure the filter center frequency is properly set in relation to the carrier frequency to make sure the lowest audio frequencies and opposite sideband are adequately suppressed by the filter skirts. Please do this correctly.
Thanks for all of us,
Jeff, WI7D
|
Don¡¯t expect miracles with the NB ! It works on some noise and some it just don¡¯t care! I would eliminate all noise in and around house first!
I run a Timewave dsp599 ( works on audio ) which makes the radio much better to listen to.
My R4C I don¡¯t have a NB in it the first IF is to narrow for stock NB to work but using the Timewave , lightning isnt to bad and I don¡¯t make any rf noise in house or if I do I can turn that light off Hihi
73s Byron AC9PA
toggle quoted message
Show quoted text
On Apr 11, 2021, at 11:20 AM, wb6ogd <garywinblad@...> wrote: ?The Drake blanker is very effective... Like Richard says it works great on ignition noise. Back in the day it made the difference between being able to hear a station or not. Now a days, there isn't much ignition noise anymore so it really doesn't do much. 73, Gary WB6OGD On 4/11/2021 7:36 AM, Richard Knoppow wrote: I can talk about the R4B. The blanker works fine on ignition noise, which was what it was mostly designed for but does nothing for the grinding line noise that is much more common. I tested it using a Tektronix pulse generator. It does work but is not like the blankers found in some more modern receivers. The idea of the blanker is to prevent pulse noise like ignition noise from causing the AVC to reduce sensitivity. It also does not affect the sort of noise a conventional noise limiter of the sort found in boatanchor receivers will take out but the usual series valve limiter does not work for CW or SSB. I think there are after market noise removers that work pretty well.
On 4/11/2021 5:09 AM, David Lipson via groups.io wrote:
Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David
N9pvf
|
The Drake blanker is very effective...? Like Richard says it works great on ignition noise.
Back in the day it made the difference between being able to hear a station or not.
Now a days, there isn't much ignition noise anymore so it really doesn't do much.
73,
Gary
WB6OGD
toggle quoted message
Show quoted text
On 4/11/2021 7:36 AM, Richard Knoppow wrote: ?? I can talk about the R4B. The blanker works fine on ignition noise, which was what it was mostly designed for but does nothing for the grinding line noise that is much more common. I tested it using a Tektronix pulse generator. It does work but is not like the blankers found in some more modern receivers. The idea of the blanker is to prevent pulse noise like ignition noise from causing the AVC to reduce sensitivity. It also does not affect the sort of noise a conventional noise limiter of the sort found in boatanchor receivers will take out but the usual series valve limiter does not work for CW or SSB. I think there are after market noise removers that work pretty well.
On 4/11/2021 5:09 AM, David Lipson via groups.io wrote:
Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David
N9pvf
|
A final consideration, of course, is to ensure the filter center frequency is properly set in relation to the carrier frequency to make sure the lowest audio frequencies and opposite sideband are adequately suppressed by the filter skirts. Please do this correctly.
Thanks for all of us,
Jeff, WI7D
|
Please disregard this message.? I posted to the wrong group.
Thanks Ryan Scott
The following files have been uploaded to
the Files area of the [email protected] group.
By: Ryan Scott <tweeker42000@...>
Description:
For any of you who attended Stan's sale last month. Here is a detailed inventory list provided to me by Valerie. It will tell you the state of the instrument you received. Thanks, Ryan Scott
|
The following files have been uploaded to
the Files area of the [email protected] group.
By: Ryan Scott <tweeker42000@...>
Description:
For any of you who attended Stan's sale last month. Here is a detailed inventory list provided to me by Valerie. It will tell you the state of the instrument you received. Thanks, Ryan Scott
|
I can talk about the R4B. The blanker works fine on ignition noise, which was what it was mostly designed for but does nothing for the grinding line noise that is much more common. I tested it using a Tektronix pulse generator. It does work but is not like the blankers found in some more modern receivers. The idea of the blanker is to prevent pulse noise like ignition noise from causing the AVC to reduce sensitivity. It also does not affect the sort of noise a conventional noise limiter of the sort found in boatanchor receivers will take out but the usual series valve limiter does not work for CW or SSB. I think there are after market noise removers that work pretty well.
toggle quoted message
Show quoted text
On 4/11/2021 5:09 AM, David Lipson via groups.io wrote: Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David
N9pvf
--
Richard Knoppow
1oldlens1@...
WB6KBL
|
Hi
I,ve been trying to use my r4a recently. The pulse noise has been strong, and the blanker does not seem to be helpful. IS the experience of others similar?
73s
David?
N9pvf
|
Greg W9GB
James Sawle (MD0MDI)
Jim Shorney
Gary WB6OGD
Ryan Scott