Teaberry T 40 Ch Hybrid

Caps, cap, capacitor, direct inject, bass, lows, hi fi, hifi, hi-fi, high fidelity, mod, mods, modification, upgrade, widen, wide audio, Goldfinger, Cobra, Galaxy, Ranger
a365
WWPDX MEMBER
Posts: 63
Joined: Tue Feb 07, 2012 2:45 am

Teaberry T 40 Ch Hybrid

Postby a365 » Mon Mar 23, 2015 8:47 am

Hello Goldfinger:

I would like to get more HiFi sounds out of this radio in TX and RX mode

Your help will be appreciated

Thank you in advance

A365/Tony



Image
User avatar
Goldfinger
Site Maintenance
Posts: 2936
Joined: Sat Jun 30, 2007 12:27 am
Location: Beaver State

Postby Goldfinger » Mon Mar 23, 2015 10:34 am

$50 :lol:


I'll dig out the SAMS and take a look. Post it up soon!
wwpdx
wwpdx.com
User avatar
Goldfinger
Site Maintenance
Posts: 2936
Joined: Sat Jun 30, 2007 12:27 am
Location: Beaver State

Postby Goldfinger » Mon Mar 23, 2015 1:14 pm

RX:

C408 - Change to a .22uF, 50 volt or higher
More highs?
C410 - Change to a 330 or 220pF, 50 volt or higher

This unit has a strange always on ANL circuit. Because of this I'm not sure if C407 also needs to be made larger without having an actual radio to play with. This cap also feeds the AGC line. If the receive seems to be lacking lows after the conversion, change C407 to a .1-.22uF, 50 volt or higher. Let me know a365 after you modify the radio and I'll edit this post accordingly. Thanks!

TX/RX:

C511 - Change to a .22uF, 250 volt or higher
If the squelch acts sluggish, lower to a .1uF
C513 - Change ta a 22uF, 25 volt or higher Electrolytic, observe polarity
C601 - Change to a .22uF, 250 volt or higher


TX:

C504 - Change to a .22uF, 250 volt or higher
More highs?
C502 - Change to a 330 or 220pF, 50 volt or higher
C905 - Change to a 4.7uF, 350 volt or higher Electrolytic, observe polarity


Disable AMC - Remove C604

Variable power - Add a 50K, 2W potentiometer in series with R904

More peak power?
C912 - Change to a 1uF, 350 volt or higher Electrolytic with the negative lead towards L907


Image
Click here for full size

Image
Click here for full size
wwpdx
wwpdx.com
a365
WWPDX MEMBER
Posts: 63
Joined: Tue Feb 07, 2012 2:45 am

Postby a365 » Mon Mar 23, 2015 11:52 pm

Hello Goldfinger:

WOW,You Da Man Goldfinger :D

You can to my rescue again plus you posted the mod for the 23 Ch version too which I happen to have in my small junker collection waiting to be restored

I do not have all the capacitors to do the mods right now,please bare with me while I place an order from Mouse-R and Evilbay

I guesstimate that will take me about a month to get back to you and post my results

BTW,I payed $66.00 on Evilbay including free shipping with a D-104 MB6 back in December

Once in a while if the radio gets to hot the receiver drops down,I read on the internet that could be related to a resistor,tube socket or a tube failing

Anyway,I got a Gemtronics GTX-5000,Gemtronics GTX-2300,Colt Midnite Special and the Teaberry Model T 40,same Panasonic chassis just for the record

Thanks again Goldfinger
a365
WWPDX MEMBER
Posts: 63
Joined: Tue Feb 07, 2012 2:45 am

Postby a365 » Thu Apr 23, 2015 1:22 pm

Hello Goldfinger:

Just an update

Is been a month since I posted the last message and I still waiting for 1 set of capacitors to star the mods on the Teaberry T40 Hybrid

Sometime next week I will get the last part to complete the mods
(slow boat from China)

Thanks again for all your help and I will get back to you with in the next 2 weeks

Regards
Tony/A365
jtrouter
WWPDX MEMBER
Posts: 2
Joined: Wed Mar 16, 2016 1:57 pm

Re: AMC tube radios

Postby jtrouter » Thu May 19, 2016 4:49 pm

Hello
First i hope this does not double post as i was almost done with my first try and all of a sudden
the post i was working on vanished?
I hope this i read by Goldfinger as i belive he is the one that came up with the mods.
I have searched for over a year looking for mods to the 40 and 23 channel tube radios and all the sister
versions. I Have both of the Robyn,Gemtronic and Teaberry twins 40&23 channnel versions as well as most
of the other 23 channel versions. Anyways I was thrilled to do the AMC mod and tested the radio both before
and after cllipping C604 and not a thing changed:(. Talk about being bummed out, So i was wondering
if you could double check the part number and verify that its C604 that needs to be clipped or removed to
remove the limiter? Just to be sure i tried it on two radios and did not change on both. I love these radios
but i really need more audio out of these and i am more than willing to try whatever you can come up with.
Thank you for reading.
Jtrouter


Disable AMC - Remove C604
User avatar
Goldfinger
Site Maintenance
Posts: 2936
Joined: Sat Jun 30, 2007 12:27 am
Location: Beaver State

Re: Teaberry T 40 Ch Hybrid

Postby Goldfinger » Thu May 19, 2016 6:29 pm

Yes, C604 is correct. It may not make any difference if you already have VR4 all the way up. Also, make sure D602 wasn't disconnected by a previous owner. Removing it also disables the AMC.
wwpdx
wwpdx.com

Return to “rx and tx mods”

Who is online

Users browsing this forum: No registered users and 1 guest